Merge branch 'master' into new-chat-drawable-channel

.config/dotnet-tools.json

@@ -2,12 +2,6 @@
   "version": 1,
   "isRoot": true,
   "tools": {
-    "dotnet-format": {
-      "version": "3.1.37601",
-      "commands": [
-        "dotnet-format"
-      ]
-    },
     "jetbrains.resharper.globaltools": {
       "version": "2022.1.0-eap10",
       "commands": [

.editorconfig

@@ -1,6 +1,14 @@
 # EditorConfig is awesome: http://editorconfig.org
 root = true
 
+[*.{csproj,props,targets}]
+charset = utf-8-bom
+end_of_line = crlf
+insert_final_newline = true
+indent_style = space
+indent_size = 2
+trim_trailing_whitespace = true
+
 [*.cs]
 end_of_line = crlf
 insert_final_newline = true
@@ -8,8 +16,19 @@ indent_style = space
 indent_size = 4
 trim_trailing_whitespace = true
 
+#license header
+file_header_template = Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.\nSee the LICENCE file in the repository root for full licence text.
+
 #Roslyn naming styles
 
+#PascalCase for public and protected members
+dotnet_naming_style.pascalcase.capitalization = pascal_case
+dotnet_naming_symbols.public_members.applicable_accessibilities = public,internal,protected,protected_internal,private_protected
+dotnet_naming_symbols.public_members.applicable_kinds = property,method,field,event
+dotnet_naming_rule.public_members_pascalcase.severity = error
+dotnet_naming_rule.public_members_pascalcase.symbols = public_members
+dotnet_naming_rule.public_members_pascalcase.style = pascalcase
+
 #camelCase for private members
 dotnet_naming_style.camelcase.capitalization = camel_case
 
@@ -172,24 +191,11 @@ csharp_style_prefer_index_operator = false:silent
 csharp_style_prefer_range_operator = false:silent
 csharp_style_prefer_switch_expression = false:none
 
-#Supressing roslyn built-in analyzers
-# Suppress: EC112
-
-#Private method is unused
-dotnet_diagnostic.IDE0051.severity = silent
-#Private member is unused
-dotnet_diagnostic.IDE0052.severity = silent
-
-#Rules for disposable
-dotnet_diagnostic.IDE0067.severity = none
-dotnet_diagnostic.IDE0068.severity = none
-dotnet_diagnostic.IDE0069.severity = none
-
-#Disable operator overloads requiring alternate named methods
-dotnet_diagnostic.CA2225.severity = none
-
-# Banned APIs
-dotnet_diagnostic.RS0030.severity = error
+[*.{yaml,yml}]
+insert_final_newline = true
+indent_style = space
+indent_size = 2
+trim_trailing_whitespace = true
 
 dotnet_diagnostic.OLOC001.words_in_name = 5
 dotnet_diagnostic.OLOC001.license_header = // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.\n// See the LICENCE file in the repository root for full licence text.

.github/workflows/ci.yml

@@ -33,6 +33,9 @@ jobs:
           path: ${{ github.workspace }}/inspectcode
           key: inspectcode-${{ hashFiles('.config/dotnet-tools.json') }}-${{ hashFiles('.github/workflows/ci.yml' ) }}
 
+      - name: Dotnet code style
+        run: dotnet build -c Debug -warnaserror osu.Desktop.slnf -p:EnforceCodeStyleInBuild=true
+
       - name: CodeFileSanity
         run: |
           # TODO: Add ignore filters and GitHub Workflow Command Reporting in CFS. That way we don't have to do this workaround.
@@ -46,10 +49,6 @@ jobs:
           done <<< $(dotnet codefilesanity)
           exit $exit_code
 
-      # Temporarily disabled due to test failures, but it won't work anyway until the tool is upgraded.
-      # - name: .NET Format (Dry Run)
-      #   run: dotnet format --dry-run --check
-
       - name: InspectCode
         run: dotnet jb inspectcode $(pwd)/osu.Desktop.slnf --no-build --output="inspectcodereport.xml" --caches-home="inspectcode" --verbosity=WARN
 
@@ -147,4 +146,4 @@ jobs:
       # cannot accept .sln(f) files as arguments.
       # Build just the main game for now.
       - name: Build
-        run: msbuild osu.iOS/osu.iOS.csproj /restore /p:Configuration=Debug
+        run: msbuild osu.iOS/osu.iOS.csproj /restore /p:Configuration=Debug

.globalconfig

@@ -0,0 +1,55 @@
+is_global = true
+
+# .NET Code Style
+# IDE styles reference: https://docs.microsoft.com/dotnet/fundamentals/code-analysis/style-rules/
+
+# IDE0001: Simplify names
+dotnet_diagnostic.IDE0001.severity = warning
+
+# IDE0002: Simplify member access
+dotnet_diagnostic.IDE0002.severity = warning
+
+# IDE0003: Remove qualification
+dotnet_diagnostic.IDE0003.severity = warning
+
+# IDE0004: Remove unnecessary cast
+dotnet_diagnostic.IDE0004.severity = warning
+
+# IDE0005: Remove unnecessary imports
+dotnet_diagnostic.IDE0005.severity = warning
+
+# IDE0034: Simplify default literal
+dotnet_diagnostic.IDE0034.severity = warning
+
+# IDE0036: Sort modifiers
+dotnet_diagnostic.IDE0036.severity = warning
+
+# IDE0040: Add accessibility modifier
+dotnet_diagnostic.IDE0040.severity = warning
+
+# IDE0049: Use keyword for type name
+dotnet_diagnostic.IDE0040.severity = warning
+
+# IDE0055: Fix formatting
+dotnet_diagnostic.IDE0055.severity = warning
+
+# IDE0051: Private method is unused
+dotnet_diagnostic.IDE0051.severity = silent
+
+# IDE0052: Private member is unused
+dotnet_diagnostic.IDE0052.severity = silent
+
+# IDE0073: File header
+dotnet_diagnostic.IDE0073.severity = warning
+
+# IDE0130: Namespace mismatch with folder
+dotnet_diagnostic.IDE0130.severity = warning
+
+# IDE1006: Naming style
+dotnet_diagnostic.IDE1006.severity = warning
+
+#Disable operator overloads requiring alternate named methods
+dotnet_diagnostic.CA2225.severity = none
+
+# Banned APIs
+dotnet_diagnostic.RS0030.severity = error

Directory.Build.props

@@ -1,4 +1,4 @@
-<!-- Contains required properties for osu!framework projects. -->
+<!-- Contains required properties for osu!framework projects. -->
 <Project>
   <PropertyGroup Label="C#">
     <LangVersion>8.0</LangVersion>

osu.Android.props

@@ -1,4 +1,4 @@
-<Project>
+<Project>
   <PropertyGroup>
     <LangVersion>8.0</LangVersion>
     <OutputPath>bin\$(Configuration)</OutputPath>
@@ -52,7 +52,7 @@
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="ppy.osu.Game.Resources" Version="2022.422.0" />
-    <PackageReference Include="ppy.osu.Framework.Android" Version="2022.430.0" />
+    <PackageReference Include="ppy.osu.Framework.Android" Version="2022.509.0" />
   </ItemGroup>
   <ItemGroup Label="Transitive Dependencies">
     <!-- Realm needs to be directly referenced in all Xamarin projects, as it will not pull in its transitive dependencies otherwise. -->

osu.Game.Rulesets.Catch.Tests/Editor/CatchSelectionBlueprintTestScene.cs

@@ -29,13 +29,14 @@ namespace osu.Game.Rulesets.Catch.Tests.Editor
 
         protected CatchSelectionBlueprintTestScene()
         {
-            EditorBeatmap = new EditorBeatmap(new CatchBeatmap
+            var catchBeatmap = new CatchBeatmap
             {
                 BeatmapInfo =
                 {
                     Ruleset = new CatchRuleset().RulesetInfo,
                 }
-            }) { Difficulty = { CircleSize = 0 } };
+            };
+            EditorBeatmap = new EditorBeatmap(catchBeatmap) { Difficulty = { CircleSize = 0 } };
             EditorBeatmap.ControlPointInfo.Add(0, new TimingControlPoint
             {
                 BeatLength = 100

osu.Game.Rulesets.Catch.Tests/Editor/TestSceneBananaShowerPlacementBlueprint.cs

@@ -55,7 +55,10 @@ namespace osu.Game.Rulesets.Catch.Tests.Editor
 
             AddMoveStep(end_time, 0);
             AddClickStep(MouseButton.Left);
+
             AddMoveStep(start_time, 0);
+            AddAssert("duration is positive", () => ((BananaShower)CurrentBlueprint.HitObject).Duration > 0);
+
             AddClickStep(MouseButton.Right);
             AddAssert("start time is correct", () => Precision.AlmostEquals(LastObject.HitObject.StartTime, start_time));
             AddAssert("end time is correct", () => Precision.AlmostEquals(LastObject.HitObject.GetEndTime(), end_time));

osu.Game.Rulesets.Catch/Edit/Blueprints/BananaShowerPlacementBlueprint.cs

@@ -1,6 +1,7 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using osu.Framework.Input.Events;
 using osu.Game.Rulesets.Catch.Edit.Blueprints.Components;
 using osu.Game.Rulesets.Catch.Objects;
@@ -13,11 +14,21 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints
     {
         private readonly TimeSpanOutline outline;
 
+        private double placementStartTime;
+        private double placementEndTime;
+
         public BananaShowerPlacementBlueprint()
         {
             InternalChild = outline = new TimeSpanOutline();
         }
 
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            BeginPlacement();
+        }
+
         protected override void Update()
         {
             base.Update();
@@ -38,13 +49,6 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints
                 case PlacementState.Active:
                     if (e.Button != MouseButton.Right) break;
 
-                    // If the duration is negative, swap the start and the end time to make the duration positive.
-                    if (HitObject.Duration < 0)
-                    {
-                        HitObject.StartTime = HitObject.EndTime;
-                        HitObject.Duration = -HitObject.Duration;
-                    }
-
                     EndPlacement(HitObject.Duration > 0);
                     return true;
             }
@@ -61,13 +65,16 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints
             switch (PlacementActive)
             {
                 case PlacementState.Waiting:
-                    HitObject.StartTime = time;
+                    placementStartTime = placementEndTime = time;
                     break;
 
                 case PlacementState.Active:
-                    HitObject.EndTime = time;
+                    placementEndTime = time;
                     break;
             }
+
+            HitObject.StartTime = Math.Min(placementStartTime, placementEndTime);
+            HitObject.EndTime = Math.Max(placementStartTime, placementEndTime);
         }
     }
 }

osu.Game.Rulesets.Catch/Edit/Blueprints/JuiceStreamPlacementBlueprint.cs

@@ -47,6 +47,8 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints
             base.LoadComplete();
 
             inputManager = GetContainingInputManager();
+
+            BeginPlacement();
         }
 
         protected override bool OnMouseDown(MouseDownEvent e)

osu.Game.Rulesets.Osu/Mods/OsuModStrictTracking.cs

@@ -107,6 +107,18 @@ namespace osu.Game.Rulesets.Osu.Mods
                 {
                     switch (e.Type)
                     {
+                        case SliderEventType.Tick:
+                            AddNested(new SliderTick
+                            {
+                                SpanIndex = e.SpanIndex,
+                                SpanStartTime = e.SpanStartTime,
+                                StartTime = e.Time,
+                                Position = Position + Path.PositionAt(e.PathProgress),
+                                StackHeight = StackHeight,
+                                Scale = Scale,
+                            });
+                            break;
+
                         case SliderEventType.Head:
                             AddNested(HeadCircle = new SliderHeadCircle
                             {

osu.Game.Tests/Mods/ModUtilsTest.cs

@@ -137,33 +137,137 @@ namespace osu.Game.Tests.Mods
             // incompatible pair.
             new object[]
             {
-                new Mod[] { new OsuModDoubleTime(), new OsuModHalfTime() },
-                new[] { typeof(OsuModDoubleTime), typeof(OsuModHalfTime) }
+                new Mod[] { new OsuModHidden(), new OsuModApproachDifferent() },
+                new[] { typeof(OsuModHidden), typeof(OsuModApproachDifferent) }
             },
             // incompatible pair with derived class.
             new object[]
             {
-                new Mod[] { new OsuModNightcore(), new OsuModHalfTime() },
-                new[] { typeof(OsuModNightcore), typeof(OsuModHalfTime) }
+                new Mod[] { new OsuModDeflate(), new OsuModApproachDifferent() },
+                new[] { typeof(OsuModDeflate), typeof(OsuModApproachDifferent) }
             },
             // system mod.
             new object[]
             {
-                new Mod[] { new OsuModDoubleTime(), new OsuModTouchDevice() },
+                new Mod[] { new OsuModHidden(), new OsuModTouchDevice() },
                 new[] { typeof(OsuModTouchDevice) }
             },
             // multi mod.
             new object[]
             {
-                new Mod[] { new MultiMod(new OsuModHalfTime()), new OsuModDaycore() },
+                new Mod[] { new MultiMod(new OsuModSuddenDeath(), new OsuModPerfect()) },
                 new[] { typeof(MultiMod) }
             },
+            // invalid multiplayer mod is valid for local.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new InvalidMultiplayerMod() },
+                null
+            },
+            // invalid free mod is valid for local.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new InvalidMultiplayerFreeMod() },
+                null
+            },
             // valid pair.
             new object[]
             {
-                new Mod[] { new OsuModDoubleTime(), new OsuModHardRock() },
+                new Mod[] { new OsuModHidden(), new OsuModHardRock() },
                 null
-            }
+            },
+        };
+
+        private static readonly object[] invalid_multiplayer_mod_test_scenarios =
+        {
+            // incompatible pair.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new OsuModApproachDifferent() },
+                new[] { typeof(OsuModHidden), typeof(OsuModApproachDifferent) }
+            },
+            // incompatible pair with derived class.
+            new object[]
+            {
+                new Mod[] { new OsuModDeflate(), new OsuModApproachDifferent() },
+                new[] { typeof(OsuModDeflate), typeof(OsuModApproachDifferent) }
+            },
+            // system mod.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new OsuModTouchDevice() },
+                new[] { typeof(OsuModTouchDevice) }
+            },
+            // multi mod.
+            new object[]
+            {
+                new Mod[] { new MultiMod(new OsuModSuddenDeath(), new OsuModPerfect()) },
+                new[] { typeof(MultiMod) }
+            },
+            // invalid multiplayer mod.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new InvalidMultiplayerMod() },
+                new[] { typeof(InvalidMultiplayerMod) }
+            },
+            // invalid free mod is valid for multiplayer global.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new InvalidMultiplayerFreeMod() },
+                null
+            },
+            // valid pair.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new OsuModHardRock() },
+                null
+            },
+        };
+
+        private static readonly object[] invalid_free_mod_test_scenarios =
+        {
+            // system mod.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new OsuModTouchDevice() },
+                new[] { typeof(OsuModTouchDevice) }
+            },
+            // multi mod.
+            new object[]
+            {
+                new Mod[] { new MultiMod(new OsuModSuddenDeath(), new OsuModPerfect()) },
+                new[] { typeof(MultiMod) }
+            },
+            // invalid multiplayer mod.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new InvalidMultiplayerMod() },
+                new[] { typeof(InvalidMultiplayerMod) }
+            },
+            // invalid free mod.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new InvalidMultiplayerFreeMod() },
+                new[] { typeof(InvalidMultiplayerFreeMod) }
+            },
+            // incompatible pair is valid for free mods.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new OsuModApproachDifferent() },
+                null,
+            },
+            // incompatible pair with derived class is valid for free mods.
+            new object[]
+            {
+                new Mod[] { new OsuModDeflate(), new OsuModSpinIn() },
+                null,
+            },
+            // valid pair.
+            new object[]
+            {
+                new Mod[] { new OsuModHidden(), new OsuModHardRock() },
+                null
+            },
         };
 
         [TestCaseSource(nameof(invalid_mod_test_scenarios))]
@@ -179,6 +283,32 @@ namespace osu.Game.Tests.Mods
                 Assert.That(invalid.Select(t => t.GetType()), Is.EquivalentTo(expectedInvalid));
         }
 
+        [TestCaseSource(nameof(invalid_multiplayer_mod_test_scenarios))]
+        public void TestInvalidMultiplayerModScenarios(Mod[] inputMods, Type[] expectedInvalid)
+        {
+            bool isValid = ModUtils.CheckValidRequiredModsForMultiplayer(inputMods, out var invalid);
+
+            Assert.That(isValid, Is.EqualTo(expectedInvalid == null));
+
+            if (isValid)
+                Assert.IsNull(invalid);
+            else
+                Assert.That(invalid.Select(t => t.GetType()), Is.EquivalentTo(expectedInvalid));
+        }
+
+        [TestCaseSource(nameof(invalid_free_mod_test_scenarios))]
+        public void TestInvalidFreeModScenarios(Mod[] inputMods, Type[] expectedInvalid)
+        {
+            bool isValid = ModUtils.CheckValidFreeModsForMultiplayer(inputMods, out var invalid);
+
+            Assert.That(isValid, Is.EqualTo(expectedInvalid == null));
+
+            if (isValid)
+                Assert.IsNull(invalid);
+            else
+                Assert.That(invalid.Select(t => t.GetType()), Is.EquivalentTo(expectedInvalid));
+        }
+
         public abstract class CustomMod1 : Mod, IModCompatibilitySpecification
         {
         }
@@ -187,6 +317,27 @@ namespace osu.Game.Tests.Mods
         {
         }
 
+        public class InvalidMultiplayerMod : Mod
+        {
+            public override string Name => string.Empty;
+            public override string Description => string.Empty;
+            public override string Acronym => string.Empty;
+            public override double ScoreMultiplier => 1;
+            public override bool HasImplementation => true;
+            public override bool ValidForMultiplayer => false;
+            public override bool ValidForMultiplayerAsFreeMod => false;
+        }
+
+        private class InvalidMultiplayerFreeMod : Mod
+        {
+            public override string Name => string.Empty;
+            public override string Description => string.Empty;
+            public override string Acronym => string.Empty;
+            public override double ScoreMultiplier => 1;
+            public override bool HasImplementation => true;
+            public override bool ValidForMultiplayerAsFreeMod => false;
+        }
+
         public interface IModCompatibilitySpecification
         {
         }

osu.Game.Tests/Visual/Background/TestSceneUserDimBackgrounds.cs

@@ -1,7 +1,6 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
-using System.Linq;
 using System.Threading;
 using NUnit.Framework;
 using osu.Framework.Allocation;
@@ -283,7 +282,7 @@ namespace osu.Game.Tests.Visual.Background
             AddUntilStep("Song select has selection", () => songSelect.Carousel?.SelectedBeatmapInfo != null);
             AddStep("Set default user settings", () =>
             {
-                SelectedMods.Value = SelectedMods.Value.Concat(new[] { new OsuModNoFail() }).ToArray();
+                SelectedMods.Value = new[] { new OsuModNoFail() };
                 songSelect.DimLevel.Value = 0.7f;
                 songSelect.BlurLevel.Value = 0.4f;
             });

osu.Game.Tests/Visual/Collections/TestSceneManageCollectionsDialog.cs

@@ -142,13 +142,12 @@ namespace osu.Game.Tests.Visual.Collections
             AddStep("add dropdown", () =>
             {
                 Add(new CollectionFilterDropdown
-                    {
-                        Anchor = Anchor.TopRight,
-                        Origin = Anchor.TopRight,
-                        RelativeSizeAxes = Axes.X,
-                        Width = 0.4f,
-                    }
-                );
+                {
+                    Anchor = Anchor.TopRight,
+                    Origin = Anchor.TopRight,
+                    RelativeSizeAxes = Axes.X,
+                    Width = 0.4f,
+                });
             });
             AddStep("add two collections with same name", () => manager.Collections.AddRange(new[]
             {

osu.Game.Tests/Visual/Gameplay/TestSceneGameplaySamplePlayback.cs

@@ -5,6 +5,7 @@ using System.Collections.Generic;
 using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Testing;
+using osu.Game.Audio;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Osu;
 using osu.Game.Rulesets.Osu.Objects.Drawables;

osu.Game.Tests/Visual/Gameplay/TestSceneSkinnableSound.cs

@@ -15,7 +15,6 @@ using osu.Framework.Graphics.OpenGL.Textures;
 using osu.Framework.Graphics.Textures;
 using osu.Framework.Testing;
 using osu.Game.Audio;
-using osu.Game.Screens.Play;
 using osu.Game.Skinning;
 
 namespace osu.Game.Tests.Visual.Gameplay
@@ -131,7 +130,6 @@ namespace osu.Game.Tests.Visual.Gameplay
         }
 
         [Cached(typeof(ISkinSource))]
-        [Cached(typeof(ISamplePlaybackDisabler))]
         private class TestSkinSourceContainer : Container, ISkinSource, ISamplePlaybackDisabler
         {
             [Resolved]

osu.Game.Tests/Visual/Multiplayer/TestSceneFreeModSelectScreen.cs

@@ -1,29 +1,37 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System.Collections.Generic;
 using System.Linq;
 using NUnit.Framework;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Testing;
+using osu.Game.Graphics.UserInterface;
 using osu.Game.Overlays.Mods;
+using osu.Game.Rulesets.Osu.Mods;
+using osu.Game.Rulesets.Mods;
 using osu.Game.Screens.OnlinePlay;
+using osuTK.Input;
 
 namespace osu.Game.Tests.Visual.Multiplayer
 {
     public class TestSceneFreeModSelectScreen : MultiplayerTestScene
     {
+        private FreeModSelectScreen freeModSelectScreen;
+        private readonly Bindable<Dictionary<ModType, IReadOnlyList<Mod>>> availableMods = new Bindable<Dictionary<ModType, IReadOnlyList<Mod>>>();
+
+        [BackgroundDependencyLoader]
+        private void load(OsuGameBase osuGameBase)
+        {
+            availableMods.BindTo(osuGameBase.AvailableMods);
+        }
+
         [Test]
         public void TestFreeModSelect()
         {
-            FreeModSelectScreen freeModSelectScreen = null;
-
-            AddStep("create free mod select screen", () => Child = freeModSelectScreen = new FreeModSelectScreen
-            {
-                State = { Value = Visibility.Visible }
-            });
-            AddUntilStep("all column content loaded",
-                () => freeModSelectScreen.ChildrenOfType<ModColumn>().Any()
-                      && freeModSelectScreen.ChildrenOfType<ModColumn>().All(column => column.IsLoaded && column.ItemsLoaded));
+            createFreeModSelect();
 
             AddUntilStep("all visible mods are playable",
                 () => this.ChildrenOfType<ModPanel>()
@@ -36,5 +44,62 @@ namespace osu.Game.Tests.Visual.Multiplayer
                     freeModSelectScreen.State.Value = visible ? Visibility.Visible : Visibility.Hidden;
             });
         }
+
+        [Test]
+        public void TestCustomisationNotAvailable()
+        {
+            createFreeModSelect();
+
+            AddStep("select difficulty adjust", () => freeModSelectScreen.SelectedMods.Value = new[] { new OsuModDifficultyAdjust() });
+            AddWaitStep("wait some", 3);
+            AddAssert("customisation area not expanded", () => this.ChildrenOfType<ModSettingsArea>().Single().Height == 0);
+        }
+
+        [Test]
+        public void TestSelectDeselectAll()
+        {
+            createFreeModSelect();
+
+            AddStep("click select all button", () =>
+            {
+                InputManager.MoveMouseTo(this.ChildrenOfType<ShearedButton>().ElementAt(1));
+                InputManager.Click(MouseButton.Left);
+            });
+            AddUntilStep("all mods selected", assertAllAvailableModsSelected);
+
+            AddStep("click deselect all button", () =>
+            {
+                InputManager.MoveMouseTo(this.ChildrenOfType<ShearedButton>().Last());
+                InputManager.Click(MouseButton.Left);
+            });
+            AddUntilStep("all mods deselected", () => !freeModSelectScreen.SelectedMods.Value.Any());
+        }
+
+        private void createFreeModSelect()
+        {
+            AddStep("create free mod select screen", () => Child = freeModSelectScreen = new FreeModSelectScreen
+            {
+                State = { Value = Visibility.Visible }
+            });
+            AddUntilStep("all column content loaded",
+                () => freeModSelectScreen.ChildrenOfType<ModColumn>().Any()
+                      && freeModSelectScreen.ChildrenOfType<ModColumn>().All(column => column.IsLoaded && column.ItemsLoaded));
+        }
+
+        private bool assertAllAvailableModsSelected()
+        {
+            var allAvailableMods = availableMods.Value
+                                                .SelectMany(pair => pair.Value)
+                                                .Where(mod => mod.UserPlayable && mod.HasImplementation)
+                                                .ToList();
+
+            foreach (var availableMod in allAvailableMods)
+            {
+                if (freeModSelectScreen.SelectedMods.Value.All(selectedMod => selectedMod.GetType() != availableMod.GetType()))
+                    return false;
+            }
+
+            return true;
+        }
     }
 }

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayer.cs

@@ -627,7 +627,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             AddStep("invoke on back button", () => multiplayerComponents.OnBackButton());
 
-            AddAssert("mod overlay is hidden", () => this.ChildrenOfType<UserModSelectOverlay>().Single().State.Value == Visibility.Hidden);
+            AddAssert("mod overlay is hidden", () => this.ChildrenOfType<UserModSelectScreen>().Single().State.Value == Visibility.Hidden);
 
             AddAssert("dialog overlay is hidden", () => DialogOverlay.State.Value == Visibility.Hidden);
 

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerMatchSongSelect.cs

@@ -132,7 +132,11 @@ namespace osu.Game.Tests.Visual.Multiplayer
         private void assertHasFreeModButton(Type type, bool hasButton = true)
         {
             AddAssert($"{type.ReadableName()} {(hasButton ? "displayed" : "not displayed")} in freemod overlay",
-                () => songSelect.ChildrenOfType<FreeModSelectOverlay>().Single().ChildrenOfType<ModButton>().All(b => b.Mod.GetType() != type));
+                () => this.ChildrenOfType<FreeModSelectScreen>()
+                          .Single()
+                          .ChildrenOfType<ModPanel>()
+                          .Where(panel => !panel.Filtered.Value)
+                          .All(b => b.Mod.GetType() != type));
         }
 
         private class TestMultiplayerMatchSongSelect : MultiplayerMatchSongSelect

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerMatchSubScreen.cs

@@ -168,8 +168,13 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             ClickButtonWhenEnabled<RoomSubScreen.UserModSelectButton>();
 
+            AddUntilStep("mod select contents loaded",
+                () => this.ChildrenOfType<ModColumn>().Any() && this.ChildrenOfType<ModColumn>().All(col => col.IsLoaded && col.ItemsLoaded));
             AddUntilStep("mod select contains only double time mod",
-                () => this.ChildrenOfType<UserModSelectOverlay>().SingleOrDefault()?.ChildrenOfType<ModButton>().SingleOrDefault()?.Mod is OsuModDoubleTime);
+                () => this.ChildrenOfType<UserModSelectScreen>()
+                          .SingleOrDefault()?
+                          .ChildrenOfType<ModPanel>()
+                          .SingleOrDefault(panel => !panel.Filtered.Value)?.Mod is OsuModDoubleTime);
         }
     }
 }

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerTeamResults.cs

@@ -8,11 +8,23 @@ using osu.Game.Online.Rooms;
 using osu.Game.Rulesets.Osu;
 using osu.Game.Screens.OnlinePlay.Multiplayer;
 using osu.Game.Tests.Resources;
+using osuTK;
 
 namespace osu.Game.Tests.Visual.Multiplayer
 {
     public class TestSceneMultiplayerTeamResults : ScreenTestScene
     {
+        [Test]
+        public void TestScaling()
+        {
+            // scheduling is needed as scaling the content immediately causes the entire scene to shake badly, for some odd reason.
+            AddSliderStep("scale", 0.5f, 1.6f, 1f, v => Schedule(() =>
+            {
+                Stack.Scale = new Vector2(v);
+                Stack.Size = new Vector2(1f / v);
+            }));
+        }
+
         [TestCase(7483253, 1048576)]
         [TestCase(1048576, 7483253)]
         [TestCase(1048576, 1048576)]

osu.Game.Tests/Visual/Navigation/TestSceneScreenNavigation.cs

@@ -11,6 +11,7 @@ using osu.Framework.Graphics.Containers;
 using osu.Framework.Screens;
 using osu.Framework.Testing;
 using osu.Game.Beatmaps;
+using osu.Game.Configuration;
 using osu.Game.Graphics.UserInterface;
 using osu.Game.Online.Leaderboards;
 using osu.Game.Overlays;
@@ -253,12 +254,12 @@ namespace osu.Game.Tests.Visual.Navigation
             PushAndConfirm(() => songSelect = new TestPlaySongSelect());
             AddStep("Show mods overlay", () => songSelect.ModSelectOverlay.Show());
             AddAssert("Overlay was shown", () => songSelect.ModSelectOverlay.State.Value == Visibility.Visible);
-            AddStep("Move mouse to backButton", () => InputManager.MoveMouseTo(backButtonPosition));
 
-            // BackButton handles hover using its child button, so this checks whether or not any of BackButton's children are hovered.
-            AddUntilStep("Back button is hovered", () => Game.ChildrenOfType<BackButton>().First().Children.Any(c => c.IsHovered));
+            AddStep("Move mouse to dimmed area", () => InputManager.MoveMouseTo(new Vector2(
+                songSelect.ScreenSpaceDrawQuad.TopLeft.X + 1,
+                songSelect.ScreenSpaceDrawQuad.TopLeft.Y + songSelect.ScreenSpaceDrawQuad.Height / 2)));
+            AddStep("Click left mouse button", () => InputManager.Click(MouseButton.Left));
 
-            AddStep("Click back button", () => InputManager.Click(MouseButton.Left));
             AddUntilStep("Overlay was hidden", () => songSelect.ModSelectOverlay.State.Value == Visibility.Hidden);
             exitViaBackButtonAndConfirm();
         }
@@ -503,6 +504,22 @@ namespace osu.Game.Tests.Visual.Navigation
             AddStep("test dispose doesn't crash", () => Game.Dispose());
         }
 
+        [Test]
+        public void TestRapidBackButtonExit()
+        {
+            AddStep("set hold delay to 0", () => Game.LocalConfig.SetValue(OsuSetting.UIHoldActivationDelay, 0.0));
+
+            AddStep("press escape twice rapidly", () =>
+            {
+                InputManager.Key(Key.Escape);
+                InputManager.Key(Key.Escape);
+            });
+
+            pushEscape();
+
+            AddAssert("exit dialog is shown", () => Game.Dependencies.Get<IDialogOverlay>().CurrentDialog != null);
+        }
+
         private Func<Player> playToResults()
         {
             Player player = null;
@@ -551,7 +568,7 @@ namespace osu.Game.Tests.Visual.Navigation
 
         public class TestPlaySongSelect : PlaySongSelect
         {
-            public ModSelectOverlay ModSelectOverlay => ModSelect;
+            public ModSelectScreen ModSelectOverlay => ModSelect;
 
             public BeatmapOptionsOverlay BeatmapOptionsOverlay => BeatmapOptions;
 

osu.Game.Tests/Visual/Navigation/TestSceneSkinEditorNavigation.cs

@@ -4,6 +4,7 @@
 using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Extensions;
+using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.UserInterface;
 using osu.Framework.Testing;
 using osu.Game.Overlays.Settings;
@@ -18,22 +19,23 @@ using static osu.Game.Tests.Visual.Navigation.TestSceneScreenNavigation;
 
 namespace osu.Game.Tests.Visual.Navigation
 {
-    public class TestSceneSkinEditorSceneLibrary : OsuGameTestScene
+    public class TestSceneSkinEditorNavigation : OsuGameTestScene
     {
-        private SkinEditor skinEditor;
+        private TestPlaySongSelect songSelect;
+        private SkinEditor skinEditor => Game.ChildrenOfType<SkinEditor>().FirstOrDefault();
 
-        public override void SetUpSteps()
+        private void advanceToSongSelect()
         {
-            base.SetUpSteps();
-
-            Screens.Select.SongSelect songSelect = null;
             PushAndConfirm(() => songSelect = new TestPlaySongSelect());
             AddUntilStep("wait for song select", () => songSelect.BeatmapSetsLoaded);
 
             AddStep("import beatmap", () => BeatmapImportHelper.LoadQuickOszIntoOsu(Game).WaitSafely());
 
             AddUntilStep("wait for selected", () => !Game.Beatmap.IsDefault);
+        }
 
+        private void openSkinEditor()
+        {
             AddStep("open skin editor", () =>
             {
                 InputManager.PressKey(Key.ControlLeft);
@@ -42,13 +44,15 @@ namespace osu.Game.Tests.Visual.Navigation
                 InputManager.ReleaseKey(Key.ControlLeft);
                 InputManager.ReleaseKey(Key.ShiftLeft);
             });
-
-            AddUntilStep("get skin editor", () => (skinEditor = Game.ChildrenOfType<SkinEditor>().FirstOrDefault()) != null);
+            AddUntilStep("skin editor loaded", () => skinEditor != null);
         }
 
         [Test]
         public void TestEditComponentDuringGameplay()
         {
+            advanceToSongSelect();
+            openSkinEditor();
+
             switchToGameplayScene();
 
             BarHitErrorMeter hitErrorMeter = null;
@@ -85,6 +89,8 @@ namespace osu.Game.Tests.Visual.Navigation
         [Test]
         public void TestAutoplayCompatibleModsRetainedOnEnteringGameplay()
         {
+            advanceToSongSelect();
+            openSkinEditor();
             AddStep("select DT", () => Game.SelectedMods.Value = new Mod[] { new OsuModDoubleTime() });
 
             switchToGameplayScene();
@@ -95,6 +101,8 @@ namespace osu.Game.Tests.Visual.Navigation
         [Test]
         public void TestAutoplayIncompatibleModsRemovedOnEnteringGameplay()
         {
+            advanceToSongSelect();
+            openSkinEditor();
             AddStep("select no fail and spun out", () => Game.SelectedMods.Value = new Mod[] { new OsuModNoFail(), new OsuModSpunOut() });
 
             switchToGameplayScene();
@@ -105,6 +113,8 @@ namespace osu.Game.Tests.Visual.Navigation
         [Test]
         public void TestDuplicateAutoplayModRemovedOnEnteringGameplay()
         {
+            advanceToSongSelect();
+            openSkinEditor();
             AddStep("select autoplay", () => Game.SelectedMods.Value = new Mod[] { new OsuModAutoplay() });
 
             switchToGameplayScene();
@@ -115,6 +125,8 @@ namespace osu.Game.Tests.Visual.Navigation
         [Test]
         public void TestCinemaModRemovedOnEnteringGameplay()
         {
+            advanceToSongSelect();
+            openSkinEditor();
             AddStep("select cinema", () => Game.SelectedMods.Value = new Mod[] { new OsuModCinema() });
 
             switchToGameplayScene();
@@ -122,6 +134,16 @@ namespace osu.Game.Tests.Visual.Navigation
             AddAssert("no mod selected", () => !((Player)Game.ScreenStack.CurrentScreen).Mods.Value.Any());
         }
 
+        [Test]
+        public void TestModOverlayClosesOnOpeningSkinEditor()
+        {
+            advanceToSongSelect();
+            AddStep("open mod overlay", () => songSelect.ModSelectOverlay.Show());
+
+            openSkinEditor();
+            AddUntilStep("mod overlay closed", () => songSelect.ModSelectOverlay.State.Value == Visibility.Hidden);
+        }
+
         private void switchToGameplayScene()
         {
             AddStep("Click gameplay scene button", () => skinEditor.ChildrenOfType<SkinEditorSceneLibrary.SceneButton>().First(b => b.Text == "Gameplay").TriggerClick());

osu.Game.Tests/Visual/Ranking/TestSceneResultsScreen.cs

@@ -56,6 +56,17 @@ namespace osu.Game.Tests.Visual.Ranking
             });
         }
 
+        [Test]
+        public void TestScaling()
+        {
+            // scheduling is needed as scaling the content immediately causes the entire scene to shake badly, for some odd reason.
+            AddSliderStep("scale", 0.5f, 1.6f, 1f, v => Schedule(() =>
+            {
+                Content.Scale = new Vector2(v);
+                Content.Size = new Vector2(1f / v);
+            }));
+        }
+
         [Test]
         public void TestResultsWithoutPlayer()
         {

osu.Game.Tests/Visual/SongSelect/TestScenePlaySongSelect.cs

@@ -8,6 +8,7 @@ using NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Audio;
 using osu.Framework.Bindables;
+using osu.Framework.Graphics.Containers;
 using osu.Framework.Platform;
 using osu.Framework.Screens;
 using osu.Framework.Testing;
@@ -18,6 +19,7 @@ using osu.Game.Extensions;
 using osu.Game.Graphics.UserInterface;
 using osu.Game.Online.API.Requests.Responses;
 using osu.Game.Overlays;
+using osu.Game.Overlays.Mods;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Osu;
@@ -918,6 +920,19 @@ namespace osu.Game.Tests.Visual.SongSelect
             AddAssert("check ruleset is correct for score", () => Ruleset.Value.OnlineID == 0);
         }
 
+        [Test]
+        public void TestModOverlayToggling()
+        {
+            changeRuleset(0);
+            createSongSelect();
+
+            AddStep("toggle mod overlay on", () => InputManager.Key(Key.F1));
+            AddUntilStep("mod overlay shown", () => songSelect.ModSelect.State.Value == Visibility.Visible);
+
+            AddStep("toggle mod overlay off", () => InputManager.Key(Key.F1));
+            AddUntilStep("mod overlay hidden", () => songSelect.ModSelect.State.Value == Visibility.Hidden);
+        }
+
         private void waitForInitialSelection()
         {
             AddUntilStep("wait for initial selection", () => !Beatmap.IsDefault);
@@ -993,6 +1008,7 @@ namespace osu.Game.Tests.Visual.SongSelect
             public WorkingBeatmap CurrentBeatmap => Beatmap.Value;
             public IWorkingBeatmap CurrentBeatmapDetailsBeatmap => BeatmapDetails.Beatmap;
             public new BeatmapCarousel Carousel => base.Carousel;
+            public new ModSelectScreen ModSelect => base.ModSelect;
 
             public new void PresentScore(ScoreInfo score) => base.PresentScore(score);
 

osu.Game.Tests/Visual/UserInterface/TestSceneModSelectScreen.cs

@@ -415,6 +415,72 @@ namespace osu.Game.Tests.Visual.UserInterface
             AddAssert("unimplemented mod panel is filtered", () => getPanelForMod(typeof(TestUnimplementedMod)).Filtered.Value);
         }
 
+        [Test]
+        public void TestDeselectAllViaButton()
+        {
+            createScreen();
+            changeRuleset(0);
+
+            AddStep("select DT + HD", () => SelectedMods.Value = new Mod[] { new OsuModDoubleTime(), new OsuModHidden() });
+            AddAssert("DT + HD selected", () => modSelectScreen.ChildrenOfType<ModPanel>().Count(panel => panel.Active.Value) == 2);
+
+            AddStep("click deselect all button", () =>
+            {
+                InputManager.MoveMouseTo(this.ChildrenOfType<ShearedButton>().Last());
+                InputManager.Click(MouseButton.Left);
+            });
+            AddUntilStep("all mods deselected", () => !SelectedMods.Value.Any());
+        }
+
+        [Test]
+        public void TestCloseViaBackButton()
+        {
+            createScreen();
+            changeRuleset(0);
+
+            AddStep("select difficulty adjust", () => SelectedMods.Value = new Mod[] { new OsuModDifficultyAdjust() });
+            assertCustomisationToggleState(disabled: false, active: true);
+            AddAssert("back button disabled", () => !this.ChildrenOfType<ShearedButton>().First().Enabled.Value);
+
+            AddStep("dismiss customisation area", () => InputManager.Key(Key.Escape));
+            AddStep("click back button", () =>
+            {
+                InputManager.MoveMouseTo(this.ChildrenOfType<ShearedButton>().First());
+                InputManager.Click(MouseButton.Left);
+            });
+            AddAssert("mod select hidden", () => modSelectScreen.State.Value == Visibility.Hidden);
+        }
+
+        [Test]
+        public void TestColumnHiding()
+        {
+            AddStep("create screen", () => Child = modSelectScreen = new UserModSelectScreen
+            {
+                RelativeSizeAxes = Axes.Both,
+                State = { Value = Visibility.Visible },
+                SelectedMods = { BindTarget = SelectedMods },
+                IsValidMod = mod => mod.Type == ModType.DifficultyIncrease || mod.Type == ModType.Conversion
+            });
+            waitForColumnLoad();
+            changeRuleset(0);
+
+            AddAssert("two columns visible", () => this.ChildrenOfType<ModColumn>().Count(col => col.IsPresent) == 2);
+
+            AddStep("unset filter", () => modSelectScreen.IsValidMod = _ => true);
+            AddAssert("all columns visible", () => this.ChildrenOfType<ModColumn>().All(col => col.IsPresent));
+
+            AddStep("filter out everything", () => modSelectScreen.IsValidMod = _ => false);
+            AddAssert("no columns visible", () => this.ChildrenOfType<ModColumn>().All(col => !col.IsPresent));
+
+            AddStep("hide", () => modSelectScreen.Hide());
+            AddStep("set filter for 3 columns", () => modSelectScreen.IsValidMod = mod => mod.Type == ModType.DifficultyReduction
+                                                                                          || mod.Type == ModType.Automation
+                                                                                          || mod.Type == ModType.Conversion);
+
+            AddStep("show", () => modSelectScreen.Show());
+            AddUntilStep("3 columns visible", () => this.ChildrenOfType<ModColumn>().Count(col => col.IsPresent) == 3);
+        }
+
         private void waitForColumnLoad() => AddUntilStep("all column content loaded",
             () => modSelectScreen.ChildrenOfType<ModColumn>().Any() && modSelectScreen.ChildrenOfType<ModColumn>().All(column => column.IsLoaded && column.ItemsLoaded));
 

osu.Game.Tests/Visual/UserInterface/TestSceneShearedOverlayContainer.cs

@@ -66,7 +66,10 @@ namespace osu.Game.Tests.Visual.UserInterface
 
         public class TestShearedOverlayContainer : ShearedOverlayContainer
         {
-            protected override OverlayColourScheme ColourScheme => OverlayColourScheme.Green;
+            public TestShearedOverlayContainer()
+                : base(OverlayColourScheme.Green)
+            {
+            }
 
             [BackgroundDependencyLoader]
             private void load()

osu.Game/Audio/ISamplePlaybackDisabler.cs

@@ -1,15 +1,18 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Game.Skinning;
 
-namespace osu.Game.Screens.Play
+namespace osu.Game.Audio
 {
     /// <summary>
     /// Allows a component to disable sample playback dynamically as required.
-    /// Handled by <see cref="PausableSkinnableSound"/>.
+    /// Automatically handled by <see cref="PausableSkinnableSound"/>.
+    /// May also be manually handled locally to particular components.
     /// </summary>
+    [Cached]
     public interface ISamplePlaybackDisabler
     {
         /// <summary>

osu.Game/Beatmaps/BeatmapOnlineLookupQueue.cs

@@ -153,7 +153,17 @@ namespace osu.Game.Beatmaps
                 }
             };
 
-            Task.Run(() => cacheDownloadRequest.PerformAsync());
+            Task.Run(async () =>
+            {
+                try
+                {
+                    await cacheDownloadRequest.PerformAsync();
+                }
+                catch
+                {
+                    // Prevent throwing unobserved exceptions, as they will be logged from the network request to the log file anyway.
+                }
+            });
         }
 
         private bool checkLocalCache(BeatmapSetInfo set, BeatmapInfo beatmapInfo)

osu.Game/Beatmaps/Formats/LegacyBeatmapDecoder.cs

@@ -431,9 +431,10 @@ namespace osu.Game.Beatmaps.Formats
                 OmitFirstBarLine = omitFirstBarSignature,
             };
 
-            bool isOsuRuleset = beatmap.BeatmapInfo.Ruleset.OnlineID == 0;
-            // scrolling rulesets use effect points rather than difficulty points for scroll speed adjustments.
-            if (!isOsuRuleset)
+            int onlineRulesetID = beatmap.BeatmapInfo.Ruleset.OnlineID;
+
+            // osu!taiko and osu!mania use effect points rather than difficulty points for scroll speed adjustments.
+            if (onlineRulesetID == 1 || onlineRulesetID == 3)
                 effectPoint.ScrollSpeed = speedMultiplier;
 
             addControlPoint(time, effectPoint, timingChange);

osu.Game/Beatmaps/Formats/LegacyBeatmapEncoder.cs

@@ -183,15 +183,15 @@ namespace osu.Game.Beatmaps.Formats
             SampleControlPoint lastRelevantSamplePoint = null;
             DifficultyControlPoint lastRelevantDifficultyPoint = null;
 
-            bool isOsuRuleset = onlineRulesetID == 0;
+            // In osu!taiko and osu!mania, a scroll speed is stored as "slider velocity" in legacy formats.
+            // In that case, a scrolling speed change is a global effect and per-hit object difficulty control points are ignored.
+            bool scrollSpeedEncodedAsSliderVelocity = onlineRulesetID == 1 || onlineRulesetID == 3;
 
             // iterate over hitobjects and pull out all required sample and difficulty changes
             extractDifficultyControlPoints(beatmap.HitObjects);
             extractSampleControlPoints(beatmap.HitObjects);
 
-            // handle scroll speed, which is stored as "slider velocity" in legacy formats.
-            // this is relevant for scrolling ruleset beatmaps.
-            if (!isOsuRuleset)
+            if (scrollSpeedEncodedAsSliderVelocity)
             {
                 foreach (var point in legacyControlPoints.EffectPoints)
                     legacyControlPoints.Add(point.Time, new DifficultyControlPoint { SliderVelocity = point.ScrollSpeed });
@@ -242,7 +242,7 @@ namespace osu.Game.Beatmaps.Formats
 
             IEnumerable<DifficultyControlPoint> collectDifficultyControlPoints(IEnumerable<HitObject> hitObjects)
             {
-                if (!isOsuRuleset)
+                if (scrollSpeedEncodedAsSliderVelocity)
                     yield break;
 
                 foreach (var hitObject in hitObjects)

osu.Game/Graphics/Containers/OsuFocusedOverlayContainer.cs

@@ -34,7 +34,7 @@ namespace osu.Game.Graphics.Containers
         protected virtual bool DimMainContent => true;
 
         [Resolved(CanBeNull = true)]
-        private OsuGame game { get; set; }
+        private IOverlayManager overlayManager { get; set; }
 
         [Resolved]
         private PreviewTrackManager previewTrackManager { get; set; }
@@ -50,8 +50,8 @@ namespace osu.Game.Graphics.Containers
 
         protected override void LoadComplete()
         {
-            if (game != null)
-                OverlayActivationMode.BindTo(game.OverlayActivationMode);
+            if (overlayManager != null)
+                OverlayActivationMode.BindTo(overlayManager.OverlayActivationMode);
 
             OverlayActivationMode.BindValueChanged(mode =>
             {
@@ -127,14 +127,14 @@ namespace osu.Game.Graphics.Containers
                     if (didChange)
                         samplePopIn?.Play();
 
-                    if (BlockScreenWideMouse && DimMainContent) game?.AddBlockingOverlay(this);
+                    if (BlockScreenWideMouse && DimMainContent) overlayManager?.ShowBlockingOverlay(this);
                     break;
 
                 case Visibility.Hidden:
                     if (didChange)
                         samplePopOut?.Play();
 
-                    if (BlockScreenWideMouse) game?.RemoveBlockingOverlay(this);
+                    if (BlockScreenWideMouse) overlayManager?.HideBlockingOverlay(this);
                     break;
             }
 
@@ -150,7 +150,7 @@ namespace osu.Game.Graphics.Containers
         protected override void Dispose(bool isDisposing)
         {
             base.Dispose(isDisposing);
-            game?.RemoveBlockingOverlay(this);
+            overlayManager?.HideBlockingOverlay(this);
         }
     }
 }

osu.Game/Localisation/CommonStrings.cs

@@ -59,6 +59,16 @@ namespace osu.Game.Localisation
         /// </summary>
         public static LocalisableString Importing => new TranslatableString(getKey(@"importing"), @"Importing...");
 
+        /// <summary>
+        /// "Deselect All"
+        /// </summary>
+        public static LocalisableString DeselectAll => new TranslatableString(getKey(@"deselect_all"), @"Deselect All");
+
+        /// <summary>
+        /// "Select All"
+        /// </summary>
+        public static LocalisableString SelectAll => new TranslatableString(getKey(@"select_all"), @"Select All");
+
         private static string getKey(string key) => $@"{prefix}:{key}";
     }
 }

osu.Game/Localisation/DifficultyMultiplierDisplayStrings.cs

@@ -0,0 +1,19 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Localisation;
+
+namespace osu.Game.Localisation
+{
+    public static class DifficultyMultiplierDisplayStrings
+    {
+        private const string prefix = @"osu.Game.Resources.Localisation.DifficultyMultiplierDisplay";
+
+        /// <summary>
+        /// "Difficulty Multiplier"
+        /// </summary>
+        public static LocalisableString DifficultyMultiplier => new TranslatableString(getKey(@"difficulty_multiplier"), @"Difficulty Multiplier");
+
+        private static string getKey(string key) => $@"{prefix}:{key}";
+    }
+}

osu.Game/Localisation/ModSelectScreenStrings.cs

@@ -0,0 +1,29 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Localisation;
+
+namespace osu.Game.Localisation
+{
+    public static class ModSelectScreenStrings
+    {
+        private const string prefix = @"osu.Game.Resources.Localisation.ModSelectScreen";
+
+        /// <summary>
+        /// "Mod Select"
+        /// </summary>
+        public static LocalisableString ModSelectTitle => new TranslatableString(getKey(@"mod_select_title"), @"Mod Select");
+
+        /// <summary>
+        /// "Mods provide different ways to enjoy gameplay. Some have an effect on the score you can achieve during ranked play. Others are just for fun."
+        /// </summary>
+        public static LocalisableString ModSelectDescription => new TranslatableString(getKey(@"mod_select_description"), @"Mods provide different ways to enjoy gameplay. Some have an effect on the score you can achieve during ranked play. Others are just for fun.");
+
+        /// <summary>
+        /// "Mod Customisation"
+        /// </summary>
+        public static LocalisableString ModCustomisation => new TranslatableString(getKey(@"mod_customisation"), @"Mod Customisation");
+
+        private static string getKey(string key) => $@"{prefix}:{key}";
+    }
+}

osu.Game/Migrations/20171019041408_InitialCreate.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20171025071459_AddMissingIndexRules.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20171119065731_AddBeatmapOnlineIDUniqueConstraint.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20171209034410_AddRulesetInfoShortName.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20180125143340_Settings.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20180131154205_AddMuteBinding.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 using Microsoft.EntityFrameworkCore.Infrastructure;
 using osu.Game.Database;
 using osu.Game.Input.Bindings;

osu.Game/Migrations/20180219060912_AddSkins.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20180529055154_RemoveUniqueHashConstraints.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20180621044111_UpdateTaikoDefaultBindings.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20180628011956_RemoveNegativeSetIDs.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20180913080842_AddRankStatus.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20181007180454_StandardizePaths.cs

@@ -1,6 +1,7 @@
-using System;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
 using Microsoft.EntityFrameworkCore.Migrations;
-using System.IO;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20181128100659_AddSkinInfoHash.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20181130113755_AddScoreInfoTables.cs

@@ -1,4 +1,7 @@
-using System;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
 using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations

osu.Game/Migrations/20190225062029_AddUserIDColumn.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20190525060824_SkinSettings.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20190605091246_AddDateAddedColumnToBeatmapSet.cs

@@ -1,4 +1,7 @@
-using System;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
 using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations

osu.Game/Migrations/20190708070844_AddBPMAndLengthColumns.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20190913104727_AddBeatmapVideo.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20200302094919_RefreshVolumeBindings.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20201019224408_AddEpilepsyWarning.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20210412045700_RefreshVolumeBindingsAgain.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20210511060743_AddSkinInstantiationInfo.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20210514062639_AddAuthorIdToBeatmapMetadata.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20210824185035_AddCountdownSettings.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/Migrations/20210912144011_AddSamplesMatchPlaybackRate.cs

@@ -1,4 +1,7 @@
-using Microsoft.EntityFrameworkCore.Migrations;
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Microsoft.EntityFrameworkCore.Migrations;
 
 namespace osu.Game.Migrations
 {

osu.Game/OsuGame.cs

@@ -63,7 +63,7 @@ namespace osu.Game
     /// The full osu! experience. Builds on top of <see cref="OsuGameBase"/> to add menus and binding logic
     /// for initial components that are generally retrieved via DI.
     /// </summary>
-    public class OsuGame : OsuGameBase, IKeyBindingHandler<GlobalAction>, ILocalUserPlayInfo, IPerformFromScreenRunner
+    public class OsuGame : OsuGameBase, IKeyBindingHandler<GlobalAction>, ILocalUserPlayInfo, IPerformFromScreenRunner, IOverlayManager
     {
         /// <summary>
         /// The amount of global offset to apply when a left/right anchored overlay is displayed (ie. settings or notifications).
@@ -171,6 +171,7 @@ namespace osu.Game
         private readonly string[] args;
 
         private readonly List<OsuFocusedOverlayContainer> focusedOverlays = new List<OsuFocusedOverlayContainer>();
+        private readonly List<OverlayContainer> externalOverlays = new List<OverlayContainer>();
 
         private readonly List<OverlayContainer> visibleBlockingOverlays = new List<OverlayContainer>();
 
@@ -183,22 +184,58 @@ namespace osu.Game
             SentryLogger = new SentryLogger(this);
         }
 
+        #region IOverlayManager
+
+        IBindable<OverlayActivation> IOverlayManager.OverlayActivationMode => OverlayActivationMode;
+
         private void updateBlockingOverlayFade() =>
             ScreenContainer.FadeColour(visibleBlockingOverlays.Any() ? OsuColour.Gray(0.5f) : Color4.White, 500, Easing.OutQuint);
 
-        public void AddBlockingOverlay(OverlayContainer overlay)
+        IDisposable IOverlayManager.RegisterBlockingOverlay(OverlayContainer overlayContainer)
+        {
+            if (overlayContainer.Parent != null)
+                throw new ArgumentException($@"Overlays registered via {nameof(IOverlayManager.RegisterBlockingOverlay)} should not be added to the scene graph.");
+
+            if (externalOverlays.Contains(overlayContainer))
+                throw new ArgumentException($@"{overlayContainer} has already been registered via {nameof(IOverlayManager.RegisterBlockingOverlay)} once.");
+
+            externalOverlays.Add(overlayContainer);
+            overlayContent.Add(overlayContainer);
+
+            if (overlayContainer is OsuFocusedOverlayContainer focusedOverlayContainer)
+                focusedOverlays.Add(focusedOverlayContainer);
+
+            return new InvokeOnDisposal(() => unregisterBlockingOverlay(overlayContainer));
+        }
+
+        void IOverlayManager.ShowBlockingOverlay(OverlayContainer overlay)
         {
             if (!visibleBlockingOverlays.Contains(overlay))
                 visibleBlockingOverlays.Add(overlay);
             updateBlockingOverlayFade();
         }
 
-        public void RemoveBlockingOverlay(OverlayContainer overlay) => Schedule(() =>
+        void IOverlayManager.HideBlockingOverlay(OverlayContainer overlay) => Schedule(() =>
         {
             visibleBlockingOverlays.Remove(overlay);
             updateBlockingOverlayFade();
         });
 
+        /// <summary>
+        /// Unregisters a blocking <see cref="OverlayContainer"/> that was not created by <see cref="OsuGame"/> itself.
+        /// </summary>
+        private void unregisterBlockingOverlay(OverlayContainer overlayContainer)
+        {
+            externalOverlays.Remove(overlayContainer);
+
+            if (overlayContainer is OsuFocusedOverlayContainer focusedOverlayContainer)
+                focusedOverlays.Remove(focusedOverlayContainer);
+
+            overlayContainer.Expire();
+        }
+
+        #endregion
+
         /// <summary>
         /// Close all game-wide overlays.
         /// </summary>
@@ -1153,6 +1190,7 @@ namespace osu.Game
                 horizontalOffset += (Content.ToLocalSpace(Notifications.ScreenSpaceDrawQuad.TopLeft).X - Content.DrawWidth) * SIDE_OVERLAY_OFFSET_RATIO;
 
             ScreenOffsetContainer.X = horizontalOffset;
+            overlayContent.X = horizontalOffset * 1.2f;
 
             MenuCursorContainer.CanShowCursor = (ScreenStack.CurrentScreen as IOsuScreen)?.CursorVisible ?? false;
         }

osu.Game/Overlays/BeatmapSet/Scores/TopScoreStatisticsSection.cs

@@ -119,7 +119,7 @@ namespace osu.Game.Overlays.BeatmapSet.Scores
                 maxComboColumn.Text = value.MaxCombo.ToLocalisableString(@"0\x");
 
                 ppColumn.Alpha = value.BeatmapInfo.Status.GrantsPerformancePoints() ? 1 : 0;
-                ppColumn.Text = value.PP?.ToLocalisableString(@"N0") ?? default(LocalisableString);
+                ppColumn.Text = value.PP?.ToLocalisableString(@"N0") ?? default;
 
                 statisticsColumns.ChildrenEnumerable = value.GetStatisticsForDisplay().Select(createStatisticsColumn);
                 modsColumn.Mods = value.Mods;

osu.Game/Overlays/Dialog/PopupDialog.cs

@@ -100,10 +100,6 @@ namespace osu.Game.Overlays.Dialog
             }
         }
 
-        // We always want dialogs to show their appear animation, so we request they start hidden.
-        // Normally this would not be required, but is here due to the manual Show() call that occurs before LoadComplete().
-        protected override bool StartHidden => true;
-
         protected PopupDialog()
         {
             RelativeSizeAxes = Axes.Both;
@@ -272,7 +268,7 @@ namespace osu.Game.Overlays.Dialog
 
         protected override void PopOut()
         {
-            if (!actionInvoked && content.IsPresent)
+            if (!actionInvoked)
                 // In the case a user did not choose an action before a hide was triggered, press the last button.
                 // This is presumed to always be a sane default "cancel" action.
                 buttonsContainer.Last().TriggerClick();

osu.Game/Overlays/FirstRunSetup/ScreenUIScale.cs

@@ -2,6 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using osu.Framework.Allocation;
 using osu.Framework.Audio;
@@ -19,6 +20,7 @@ using osu.Game.Graphics.UserInterface;
 using osu.Game.Localisation;
 using osu.Game.Overlays.Settings;
 using osu.Game.Rulesets;
+using osu.Game.Rulesets.Mods;
 using osu.Game.Screens;
 using osu.Game.Screens.Menu;
 using osu.Game.Screens.Select;
@@ -131,6 +133,10 @@ namespace osu.Game.Overlays.FirstRunSetup
             [Cached(typeof(IBindable<WorkingBeatmap>))]
             protected Bindable<WorkingBeatmap> Beatmap { get; private set; } = new Bindable<WorkingBeatmap>();
 
+            [Cached]
+            [Cached(typeof(IBindable<IReadOnlyList<Mod>>))]
+            protected Bindable<IReadOnlyList<Mod>> SelectedMods { get; private set; } = new Bindable<IReadOnlyList<Mod>>(Array.Empty<Mod>());
+
             public override bool HandlePositionalInput => false;
             public override bool HandleNonPositionalInput => false;
             public override bool PropagatePositionalInputSubTree => false;

osu.Game/Overlays/FirstRunSetupOverlay.cs

@@ -31,8 +31,6 @@ namespace osu.Game.Overlays
     [Cached]
     public class FirstRunSetupOverlay : ShearedOverlayContainer
     {
-        protected override OverlayColourScheme ColourScheme => OverlayColourScheme.Purple;
-
         [Resolved]
         private IPerformFromScreenRunner performer { get; set; } = null!;
 
@@ -70,6 +68,11 @@ namespace osu.Game.Overlays
 
         private Container content = null!;
 
+        public FirstRunSetupOverlay()
+            : base(OverlayColourScheme.Purple)
+        {
+        }
+
         [BackgroundDependencyLoader]
         private void load(OsuColour colours)
         {

osu.Game/Overlays/IOverlayManager.cs

@@ -0,0 +1,44 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics.Containers;
+using osu.Game.Screens.Select;
+
+namespace osu.Game.Overlays
+{
+    [Cached]
+    internal interface IOverlayManager
+    {
+        /// <summary>
+        /// Whether overlays should be able to be opened game-wide. Value is sourced from the current active screen.
+        /// </summary>
+        IBindable<OverlayActivation> OverlayActivationMode { get; }
+
+        /// <summary>
+        /// Registers a blocking <see cref="OverlayContainer"/> that was not created by <see cref="OsuGame"/> itself for later use.
+        /// </summary>
+        /// <remarks>
+        /// The goal of this method is to allow child screens, like <see cref="SongSelect"/> to register their own full-screen blocking overlays
+        /// with background dim.
+        /// In those cases, for the dim to work correctly, the overlays need to be added at a game level directly, rather as children of the screens.
+        /// </remarks>
+        /// <returns>
+        /// An <see cref="IDisposable"/> that should be disposed of when the <paramref name="overlayContainer"/> should be unregistered.
+        /// Disposing of this <see cref="IDisposable"/> will automatically expire the <paramref name="overlayContainer"/>.
+        /// </returns>
+        IDisposable RegisterBlockingOverlay(OverlayContainer overlayContainer);
+
+        /// <summary>
+        /// Should be called when <paramref name="overlay"/> has been shown and should begin blocking background input.
+        /// </summary>
+        void ShowBlockingOverlay(OverlayContainer overlay);
+
+        /// <summary>
+        /// Should be called when a blocking <paramref name="overlay"/> has been hidden and should stop blocking background input.
+        /// </summary>
+        void HideBlockingOverlay(OverlayContainer overlay);
+    }
+}

osu.Game/Overlays/Mods/DifficultyMultiplierDisplay.cs

@@ -15,6 +15,7 @@ using osu.Game.Graphics.Sprites;
 using osu.Game.Graphics.UserInterface;
 using osu.Game.Rulesets.Mods;
 using osuTK;
+using osu.Game.Localisation;
 
 namespace osu.Game.Overlays.Mods
 {
@@ -99,7 +100,7 @@ namespace osu.Game.Overlays.Mods
                                             Origin = Anchor.Centre,
                                             Margin = new MarginPadding { Horizontal = 18 },
                                             Shear = new Vector2(-ShearedOverlayContainer.SHEAR, 0),
-                                            Text = "Difficulty Multiplier",
+                                            Text = DifficultyMultiplierDisplayStrings.DifficultyMultiplier,
                                             Font = OsuFont.Default.With(size: 17, weight: FontWeight.SemiBold)
                                         }
                                     }

osu.Game/Overlays/Mods/ModColumn.cs

@@ -5,6 +5,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
@@ -22,6 +23,7 @@ using osu.Framework.Input.Events;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Containers;
 using osu.Game.Graphics.UserInterface;
+using osu.Game.Localisation;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Utils;
 using osuTK;
@@ -39,7 +41,7 @@ namespace osu.Game.Overlays.Mods
         private Func<Mod, bool>? filter;
 
         /// <summary>
-        /// Function determining whether each mod in the column should be displayed.
+        /// A function determining whether each mod in the column should be displayed.
         /// A return value of <see langword="true"/> means that the mod is not filtered and therefore its corresponding panel should be displayed.
         /// A return value of <see langword="false"/> means that the mod is filtered out and therefore its corresponding panel should be hidden.
         /// </summary>
@@ -49,12 +51,22 @@ namespace osu.Game.Overlays.Mods
             set
             {
                 filter = value;
-                updateFilter();
+                updateState();
             }
         }
 
+        /// <summary>
+        /// Determines whether this column should accept user input.
+        /// </summary>
         public Bindable<bool> Active = new BindableBool(true);
 
+        private readonly Bindable<bool> allFiltered = new BindableBool();
+
+        /// <summary>
+        /// True if all of the panels in this column have been filtered out by the current <see cref="Filter"/>.
+        /// </summary>
+        public IBindable<bool> AllFiltered => allFiltered;
+
         /// <summary>
         /// List of mods marked as selected in this column.
         /// </summary>
@@ -186,7 +198,7 @@ namespace osu.Game.Overlays.Mods
                                             },
                                             new Drawable[]
                                             {
-                                                new NestedVerticalScrollContainer
+                                                new OsuScrollContainer(Direction.Vertical)
                                                 {
                                                     RelativeSizeAxes = Axes.Both,
                                                     ClampExtension = 100,
@@ -220,7 +232,6 @@ namespace osu.Game.Overlays.Mods
                     Origin = Anchor.CentreLeft,
                     Scale = new Vector2(0.8f),
                     RelativeSizeAxes = Axes.X,
-                    LabelText = "Enable All",
                     Shear = new Vector2(-ShearedOverlayContainer.SHEAR, 0)
                 });
                 panelFlow.Padding = new MarginPadding
@@ -249,9 +260,8 @@ namespace osu.Game.Overlays.Mods
         private void load(OsuGameBase game, OverlayColourProvider colourProvider, OsuColour colours)
         {
             availableMods.BindTo(game.AvailableMods);
-            // this `BindValueChanged` callback is intentionally here, to ensure that local available mods are constructed as early as possible.
-            // this is needed to make sure no external changes to mods are dropped while mod panels are asynchronously loading.
-            availableMods.BindValueChanged(_ => updateLocalAvailableMods(), true);
+            updateLocalAvailableMods(asyncLoadContent: false);
+            availableMods.BindValueChanged(_ => updateLocalAvailableMods(asyncLoadContent: true));
 
             headerBackground.Colour = accentColour = colours.ForModType(ModType);
 
@@ -265,7 +275,20 @@ namespace osu.Game.Overlays.Mods
             contentBackground.Colour = colourProvider.Background4;
         }
 
-        private void updateLocalAvailableMods()
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            toggleAllCheckbox?.Current.BindValueChanged(_ => updateToggleAllText(), true);
+        }
+
+        private void updateToggleAllText()
+        {
+            Debug.Assert(toggleAllCheckbox != null);
+            toggleAllCheckbox.LabelText = toggleAllCheckbox.Current.Value ? CommonStrings.DeselectAll : CommonStrings.SelectAll;
+        }
+
+        private void updateLocalAvailableMods(bool asyncLoadContent)
         {
             var newMods = ModUtils.FlattenMods(availableMods.Value.GetValueOrDefault(ModType) ?? Array.Empty<Mod>())
                                   .Select(m => m.DeepClone())
@@ -275,32 +298,24 @@ namespace osu.Game.Overlays.Mods
                 return;
 
             localAvailableMods = newMods;
-            Scheduler.AddOnce(loadPanels);
+
+            if (asyncLoadContent)
+                asyncLoadPanels();
+            else
+                onPanelsLoaded(createPanels());
         }
 
         private CancellationTokenSource? cancellationTokenSource;
 
-        private void loadPanels()
+        private void asyncLoadPanels()
         {
             cancellationTokenSource?.Cancel();
 
-            var panels = localAvailableMods.Select(mod => CreateModPanel(mod).With(panel => panel.Shear = new Vector2(-ShearedOverlayContainer.SHEAR, 0)));
+            var panels = createPanels();
 
             Task? loadTask;
 
-            latestLoadTask = loadTask = LoadComponentsAsync(panels, loaded =>
-            {
-                panelFlow.ChildrenEnumerable = loaded;
-
-                updateActiveState();
-                updateToggleAllState();
-                updateFilter();
-
-                foreach (var panel in panelFlow)
-                {
-                    panel.Active.BindValueChanged(_ => panelStateChanged(panel));
-                }
-            }, (cancellationTokenSource = new CancellationTokenSource()).Token);
+            latestLoadTask = loadTask = LoadComponentsAsync(panels, onPanelsLoaded, (cancellationTokenSource = new CancellationTokenSource()).Token);
             loadTask.ContinueWith(_ =>
             {
                 if (loadTask == latestLoadTask)
@@ -308,10 +323,39 @@ namespace osu.Game.Overlays.Mods
             });
         }
 
-        private void updateActiveState()
+        private IEnumerable<ModPanel> createPanels()
+        {
+            var panels = localAvailableMods.Select(mod => CreateModPanel(mod).With(panel => panel.Shear = new Vector2(-ShearedOverlayContainer.SHEAR, 0)));
+            return panels;
+        }
+
+        private void onPanelsLoaded(IEnumerable<ModPanel> loaded)
+        {
+            panelFlow.ChildrenEnumerable = loaded;
+
+            updateState();
+
+            foreach (var panel in panelFlow)
+            {
+                panel.Active.BindValueChanged(_ => panelStateChanged(panel));
+            }
+        }
+
+        private void updateState()
         {
             foreach (var panel in panelFlow)
+            {
                 panel.Active.Value = SelectedMods.Contains(panel.Mod);
+                panel.ApplyFilter(Filter);
+            }
+
+            allFiltered.Value = panelFlow.All(panel => panel.Filtered.Value);
+
+            if (toggleAllCheckbox != null && !SelectionAnimationRunning)
+            {
+                toggleAllCheckbox.Alpha = panelFlow.Any(panel => !panel.Filtered.Value) ? 1 : 0;
+                toggleAllCheckbox.Current.Value = panelFlow.Where(panel => !panel.Filtered.Value).All(panel => panel.Active.Value);
+            }
         }
 
         /// <summary>
@@ -323,15 +367,16 @@ namespace osu.Game.Overlays.Mods
 
         private void panelStateChanged(ModPanel panel)
         {
-            updateToggleAllState();
+            if (externalSelectionUpdateInProgress)
+                return;
 
             var newSelectedMods = panel.Active.Value
                 ? SelectedMods.Append(panel.Mod)
                 : SelectedMods.Except(panel.Mod.Yield());
 
             SelectedMods = newSelectedMods.ToArray();
-            if (!externalSelectionUpdateInProgress)
-                SelectionChangedByUser?.Invoke();
+            updateState();
+            SelectionChangedByUser?.Invoke();
         }
 
         /// <summary>
@@ -364,7 +409,7 @@ namespace osu.Game.Overlays.Mods
             }
 
             SelectedMods = newSelection;
-            updateActiveState();
+            updateState();
 
             externalSelectionUpdateInProgress = false;
         }
@@ -378,7 +423,7 @@ namespace osu.Game.Overlays.Mods
 
         private readonly Queue<Action> pendingSelectionOperations = new Queue<Action>();
 
-        protected bool SelectionAnimationRunning => pendingSelectionOperations.Count > 0;
+        internal bool SelectionAnimationRunning => pendingSelectionOperations.Count > 0;
 
         protected override void Update()
         {
@@ -403,15 +448,6 @@ namespace osu.Game.Overlays.Mods
             }
         }
 
-        private void updateToggleAllState()
-        {
-            if (toggleAllCheckbox != null && !SelectionAnimationRunning)
-            {
-                toggleAllCheckbox.Alpha = panelFlow.Any(panel => !panel.Filtered.Value) ? 1 : 0;
-                toggleAllCheckbox.Current.Value = panelFlow.Where(panel => !panel.Filtered.Value).All(panel => panel.Active.Value);
-            }
-        }
-
         /// <summary>
         /// Selects all mods.
         /// </summary>
@@ -507,18 +543,6 @@ namespace osu.Game.Overlays.Mods
 
         #endregion
 
-        #region Filtering support
-
-        private void updateFilter()
-        {
-            foreach (var modPanel in panelFlow)
-                modPanel.ApplyFilter(Filter);
-
-            updateToggleAllState();
-        }
-
-        #endregion
-
         #region Keyboard selection support
 
         protected override bool OnKeyDown(KeyDownEvent e)

osu.Game/Overlays/Mods/ModPanel.cs

@@ -1,6 +1,8 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+#nullable enable
+
 using System;
 using osu.Framework.Allocation;
 using osu.Framework.Audio;
@@ -12,6 +14,7 @@ using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
 using osu.Framework.Input.Events;
 using osu.Framework.Utils;
+using osu.Game.Audio;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Containers;
 using osu.Game.Graphics.Sprites;
@@ -21,8 +24,6 @@ using osu.Game.Rulesets.UI;
 using osuTK;
 using osuTK.Input;
 
-#nullable enable
-
 namespace osu.Game.Overlays.Mods
 {
     public class ModPanel : OsuClickableContainer
@@ -50,6 +51,7 @@ namespace osu.Game.Overlays.Mods
 
         private Colour4 activeColour;
 
+        private readonly Bindable<bool> samplePlaybackDisabled = new BindableBool();
         private Sample? sampleOff;
         private Sample? sampleOn;
 
@@ -139,13 +141,16 @@ namespace osu.Game.Overlays.Mods
             Action = Active.Toggle;
         }
 
-        [BackgroundDependencyLoader]
-        private void load(AudioManager audio, OsuColour colours)
+        [BackgroundDependencyLoader(true)]
+        private void load(AudioManager audio, OsuColour colours, ISamplePlaybackDisabler? samplePlaybackDisabler)
         {
             sampleOn = audio.Samples.Get(@"UI/check-on");
             sampleOff = audio.Samples.Get(@"UI/check-off");
 
             activeColour = colours.ForModType(Mod.Type);
+
+            if (samplePlaybackDisabler != null)
+                ((IBindable<bool>)samplePlaybackDisabled).BindTo(samplePlaybackDisabler.SamplePlaybackDisabled);
         }
 
         protected override HoverSounds CreateHoverSounds(HoverSampleSet sampleSet) => new HoverSounds(sampleSet);
@@ -166,6 +171,9 @@ namespace osu.Game.Overlays.Mods
 
         private void playStateChangeSamples()
         {
+            if (samplePlaybackDisabled.Value)
+                return;
+
             if (Active.Value)
                 sampleOn?.Play();
             else

osu.Game/Overlays/Mods/ModSelectScreen.cs

@@ -13,27 +13,35 @@ using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Input.Events;
 using osu.Framework.Layout;
+using osu.Framework.Lists;
 using osu.Framework.Utils;
+using osu.Game.Audio;
 using osu.Game.Configuration;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Containers;
 using osu.Game.Graphics.UserInterface;
 using osu.Game.Input.Bindings;
+using osu.Game.Localisation;
 using osu.Game.Rulesets.Mods;
 using osuTK;
 using osuTK.Input;
 
 namespace osu.Game.Overlays.Mods
 {
-    public abstract class ModSelectScreen : ShearedOverlayContainer
+    public abstract class ModSelectScreen : ShearedOverlayContainer, ISamplePlaybackDisabler
     {
-        protected override OverlayColourScheme ColourScheme => OverlayColourScheme.Green;
+        protected const int BUTTON_WIDTH = 200;
 
         [Cached]
         public Bindable<IReadOnlyList<Mod>> SelectedMods { get; private set; } = new Bindable<IReadOnlyList<Mod>>(Array.Empty<Mod>());
 
         private Func<Mod, bool> isValidMod = m => true;
 
+        /// <summary>
+        /// A function determining whether each mod in the column should be displayed.
+        /// A return value of <see langword="true"/> means that the mod is not filtered and therefore its corresponding panel should be displayed.
+        /// A return value of <see langword="false"/> means that the mod is filtered out and therefore its corresponding panel should be hidden.
+        /// </summary>
         public Func<Mod, bool> IsValidMod
         {
             get => isValidMod;
@@ -46,11 +54,6 @@ namespace osu.Game.Overlays.Mods
             }
         }
 
-        /// <summary>
-        /// Whether configurable <see cref="Mod"/>s can be configured by the local user.
-        /// </summary>
-        protected virtual bool AllowCustomisation => true;
-
         /// <summary>
         /// Whether the total score multiplier calculated from the current selected set of mods should be shown.
         /// </summary>
@@ -58,18 +61,32 @@ namespace osu.Game.Overlays.Mods
 
         protected virtual ModColumn CreateModColumn(ModType modType, Key[]? toggleKeys = null) => new ModColumn(modType, false, toggleKeys);
 
+        protected virtual IReadOnlyList<Mod> ComputeNewModsFromSelection(IReadOnlyList<Mod> oldSelection, IReadOnlyList<Mod> newSelection) => newSelection;
+
+        protected virtual IEnumerable<ShearedButton> CreateFooterButtons() => createDefaultFooterButtons();
+
         private readonly BindableBool customisationVisible = new BindableBool();
 
-        private DifficultyMultiplierDisplay? multiplierDisplay;
         private ModSettingsArea modSettingsArea = null!;
         private ColumnScrollContainer columnScroll = null!;
         private ColumnFlowContainer columnFlow = null!;
+        private FillFlowContainer<ShearedButton> footerButtonFlow = null!;
+        private ShearedButton backButton = null!;
+
+        private DifficultyMultiplierDisplay? multiplierDisplay;
+
+        private ShearedToggleButton? customisationButton;
+
+        protected ModSelectScreen(OverlayColourScheme colourScheme = OverlayColourScheme.Green)
+            : base(colourScheme)
+        {
+        }
 
         [BackgroundDependencyLoader]
-        private void load()
+        private void load(OsuColour colours)
         {
-            Header.Title = "Mod Select";
-            Header.Description = "Mods provide different ways to enjoy gameplay. Some have an effect on the score you can achieve during ranked play. Others are just for fun.";
+            Header.Title = ModSelectScreenStrings.ModSelectTitle;
+            Header.Description = ModSelectScreenStrings.ModSelectDescription;
 
             AddRange(new Drawable[]
             {
@@ -94,6 +111,7 @@ namespace osu.Game.Overlays.Mods
                     Padding = new MarginPadding
                     {
                         Top = (ShowTotalMultiplier ? DifficultyMultiplierDisplay.HEIGHT : 0) + PADDING,
+                        Bottom = PADDING
                     },
                     RelativeSizeAxes = Axes.Both,
                     RelativePositionAxes = Axes.Both,
@@ -111,7 +129,6 @@ namespace osu.Game.Overlays.Mods
                                 Shear = new Vector2(SHEAR, 0),
                                 RelativeSizeAxes = Axes.Y,
                                 AutoSizeAxes = Axes.X,
-                                Spacing = new Vector2(10, 0),
                                 Margin = new MarginPadding { Horizontal = 70 },
                                 Children = new[]
                                 {
@@ -144,31 +161,35 @@ namespace osu.Game.Overlays.Mods
                 });
             }
 
-            if (AllowCustomisation)
+            FooterContent.Child = footerButtonFlow = new FillFlowContainer<ShearedButton>
             {
-                Footer.Add(new ShearedToggleButton(200)
+                RelativeSizeAxes = Axes.X,
+                AutoSizeAxes = Axes.Y,
+                Direction = FillDirection.Horizontal,
+                Anchor = Anchor.BottomLeft,
+                Origin = Anchor.BottomLeft,
+                Padding = new MarginPadding
                 {
-                    Anchor = Anchor.BottomLeft,
-                    Origin = Anchor.BottomLeft,
-                    Margin = new MarginPadding { Vertical = PADDING, Left = 70 },
-                    Text = "Mod Customisation",
-                    Active = { BindTarget = customisationVisible }
-                });
-            }
-        }
-
-        private ColumnDimContainer createModColumnContent(ModType modType, Key[]? toggleKeys = null)
-            => new ColumnDimContainer(CreateModColumn(modType, toggleKeys))
-            {
-                AutoSizeAxes = Axes.X,
-                RelativeSizeAxes = Axes.Y,
-                RequestScroll = column => columnScroll.ScrollIntoView(column, extraScroll: 140)
+                    Vertical = PADDING,
+                    Horizontal = 70
+                },
+                Spacing = new Vector2(10),
+                ChildrenEnumerable = CreateFooterButtons().Prepend(backButton = new ShearedButton(BUTTON_WIDTH)
+                {
+                    Text = CommonStrings.Back,
+                    Action = Hide,
+                    DarkerColour = colours.Pink2,
+                    LighterColour = colours.Pink1
+                })
             };
+        }
 
         protected override void LoadComplete()
         {
             base.LoadComplete();
 
+            State.BindValueChanged(_ => samplePlaybackDisabled.Value = State.Value == Visibility.Hidden, true);
+
             ((IBindable<IReadOnlyList<Mod>>)modSettingsArea.SelectedMods).BindTo(SelectedMods);
 
             SelectedMods.BindValueChanged(val =>
@@ -186,8 +207,66 @@ namespace osu.Game.Overlays.Mods
             customisationVisible.BindValueChanged(_ => updateCustomisationVisualState(), true);
 
             updateAvailableMods();
+
+            // Start scrolled slightly to the right to give the user a sense that
+            // there is more horizontal content available.
+            ScheduleAfterChildren(() =>
+            {
+                columnScroll.ScrollTo(200, false);
+                columnScroll.ScrollToStart();
+            });
         }
 
+        /// <summary>
+        /// Select all visible mods in all columns.
+        /// </summary>
+        protected void SelectAll()
+        {
+            foreach (var column in columnFlow.Columns)
+                column.SelectAll();
+        }
+
+        /// <summary>
+        /// Deselect all visible mods in all columns.
+        /// </summary>
+        protected void DeselectAll()
+        {
+            foreach (var column in columnFlow.Columns)
+                column.DeselectAll();
+        }
+
+        private ColumnDimContainer createModColumnContent(ModType modType, Key[]? toggleKeys = null)
+        {
+            var column = CreateModColumn(modType, toggleKeys).With(column =>
+            {
+                column.Filter = IsValidMod;
+                // spacing applied here rather than via `columnFlow.Spacing` to avoid uneven gaps when some of the columns are hidden.
+                column.Margin = new MarginPadding { Right = 10 };
+            });
+
+            return new ColumnDimContainer(column)
+            {
+                AutoSizeAxes = Axes.X,
+                RelativeSizeAxes = Axes.Y,
+                RequestScroll = col => columnScroll.ScrollIntoView(col, extraScroll: 140),
+            };
+        }
+
+        private ShearedButton[] createDefaultFooterButtons()
+            => new[]
+            {
+                customisationButton = new ShearedToggleButton(BUTTON_WIDTH)
+                {
+                    Text = ModSelectScreenStrings.ModCustomisation,
+                    Active = { BindTarget = customisationVisible }
+                },
+                new ShearedButton(BUTTON_WIDTH)
+                {
+                    Text = CommonStrings.DeselectAll,
+                    Action = DeselectAll
+                }
+            };
+
         private void updateMultiplier()
         {
             if (multiplierDisplay == null)
@@ -209,7 +288,7 @@ namespace osu.Game.Overlays.Mods
 
         private void updateCustomisation(ValueChangedEvent<IReadOnlyList<Mod>> valueChangedEvent)
         {
-            if (!AllowCustomisation)
+            if (customisationButton == null)
                 return;
 
             bool anyCustomisableMod = false;
@@ -243,6 +322,12 @@ namespace osu.Game.Overlays.Mods
 
             MainAreaContent.FadeColour(customisationVisible.Value ? Colour4.Gray : Colour4.White, transition_duration, Easing.InOutCubic);
 
+            foreach (var button in footerButtonFlow)
+            {
+                if (button != customisationButton)
+                    button.Enabled.Value = !customisationVisible.Value;
+            }
+
             float modAreaHeight = customisationVisible.Value ? ModSettingsArea.HEIGHT : 0;
 
             modSettingsArea.ResizeHeightTo(modAreaHeight, transition_duration, Easing.InOutCubic);
@@ -264,13 +349,17 @@ namespace osu.Game.Overlays.Mods
         {
             var candidateSelection = columnFlow.Columns.SelectMany(column => column.SelectedMods).ToArray();
 
-            if (candidateSelection.SequenceEqual(SelectedMods.Value))
+            // the following guard intends to check cases where we've already replaced potentially-external mod references with our own and avoid endless recursion.
+            // TODO: replace custom comparer with System.Collections.Generic.ReferenceEqualityComparer when fully on .NET 6
+            if (candidateSelection.SequenceEqual(SelectedMods.Value, new FuncEqualityComparer<Mod>(ReferenceEquals)))
                 return;
 
             SelectedMods.Value = ComputeNewModsFromSelection(SelectedMods.Value, candidateSelection);
         }
 
-        protected virtual IReadOnlyList<Mod> ComputeNewModsFromSelection(IReadOnlyList<Mod> oldSelection, IReadOnlyList<Mod> newSelection) => newSelection;
+        #region Transition handling
+
+        private const float distance = 700;
 
         protected override void PopIn()
         {
@@ -283,13 +372,26 @@ namespace osu.Game.Overlays.Mods
                 .FadeIn(fade_in_duration / 2, Easing.OutQuint)
                 .ScaleTo(1, fade_in_duration, Easing.OutElastic);
 
+            int nonFilteredColumnCount = 0;
+
             for (int i = 0; i < columnFlow.Count; i++)
             {
-                columnFlow[i].Column
-                             .TopLevelContent
-                             .Delay(i * 30)
-                             .MoveToY(0, fade_in_duration, Easing.OutQuint)
-                             .FadeIn(fade_in_duration, Easing.OutQuint);
+                var column = columnFlow[i].Column;
+
+                double delay = column.AllFiltered.Value ? 0 : nonFilteredColumnCount * 30;
+                double duration = column.AllFiltered.Value ? 0 : fade_in_duration;
+                float startingYPosition = 0;
+                if (!column.AllFiltered.Value)
+                    startingYPosition = nonFilteredColumnCount % 2 == 0 ? -distance : distance;
+
+                column.TopLevelContent
+                      .MoveToY(startingYPosition)
+                      .Delay(delay)
+                      .MoveToY(0, duration, Easing.OutQuint)
+                      .FadeIn(duration, Easing.OutQuint);
+
+                if (!column.AllFiltered.Value)
+                    nonFilteredColumnCount += 1;
             }
         }
 
@@ -303,30 +405,83 @@ namespace osu.Game.Overlays.Mods
                 .FadeOut(fade_out_duration / 2, Easing.OutQuint)
                 .ScaleTo(0.75f, fade_out_duration, Easing.OutQuint);
 
+            int nonFilteredColumnCount = 0;
+
             for (int i = 0; i < columnFlow.Count; i++)
             {
-                const float distance = 700;
-
                 var column = columnFlow[i].Column;
 
+                double duration = column.AllFiltered.Value ? 0 : fade_out_duration;
+                float newYPosition = 0;
+                if (!column.AllFiltered.Value)
+                    newYPosition = nonFilteredColumnCount % 2 == 0 ? -distance : distance;
+
                 column.FlushPendingSelections();
                 column.TopLevelContent
-                      .MoveToY(i % 2 == 0 ? -distance : distance, fade_out_duration, Easing.OutQuint)
-                      .FadeOut(fade_out_duration, Easing.OutQuint);
+                      .MoveToY(newYPosition, duration, Easing.OutQuint)
+                      .FadeOut(duration, Easing.OutQuint);
+
+                if (!column.AllFiltered.Value)
+                    nonFilteredColumnCount += 1;
             }
         }
 
+        #endregion
+
+        #region Input handling
+
         public override bool OnPressed(KeyBindingPressEvent<GlobalAction> e)
         {
-            if (e.Action == GlobalAction.Back && customisationVisible.Value)
+            if (e.Repeat)
+                return false;
+
+            switch (e.Action)
             {
-                customisationVisible.Value = false;
-                return true;
+                case GlobalAction.Back:
+                    // Pressing the back binding should only go back one step at a time.
+                    hideOverlay(false);
+                    return true;
+
+                // This is handled locally here because this overlay is being registered at the game level
+                // and therefore takes away keyboard focus from the screen stack.
+                case GlobalAction.ToggleModSelection:
+                case GlobalAction.Select:
+                {
+                    // Pressing toggle or select should completely hide the overlay in one shot.
+                    hideOverlay(true);
+                    return true;
+                }
             }
 
             return base.OnPressed(e);
+
+            void hideOverlay(bool immediate)
+            {
+                if (customisationVisible.Value)
+                {
+                    Debug.Assert(customisationButton != null);
+                    customisationButton.TriggerClick();
+
+                    if (!immediate)
+                        return;
+                }
+
+                backButton.TriggerClick();
+            }
         }
 
+        #endregion
+
+        #region Sample playback control
+
+        private readonly Bindable<bool> samplePlaybackDisabled = new BindableBool(true);
+        IBindable<bool> ISamplePlaybackDisabler.SamplePlaybackDisabled => samplePlaybackDisabled;
+
+        #endregion
+
+        /// <summary>
+        /// Manages horizontal scrolling of mod columns, along with the "active" states of each column based on visibility.
+        /// </summary>
         internal class ColumnScrollContainer : OsuScrollContainer<ColumnFlowContainer>
         {
             public ColumnScrollContainer()
@@ -365,6 +520,9 @@ namespace osu.Game.Overlays.Mods
             }
         }
 
+        /// <summary>
+        /// Manages padding and layout of mod columns.
+        /// </summary>
         internal class ColumnFlowContainer : FillFlowContainer<ColumnDimContainer>
         {
             public IEnumerable<ModColumn> Columns => Children.Select(dimWrapper => dimWrapper.Column);
@@ -401,11 +559,21 @@ namespace osu.Game.Overlays.Mods
             }
         }
 
+        /// <summary>
+        /// Encapsulates a column and provides dim and input blocking based on an externally managed "active" state.
+        /// </summary>
         internal class ColumnDimContainer : Container
         {
             public ModColumn Column { get; }
 
+            /// <summary>
+            /// Tracks whether this column is in an interactive state. Generally only the case when the column is on-screen.
+            /// </summary>
             public readonly Bindable<bool> Active = new BindableBool();
+
+            /// <summary>
+            /// Invoked when the column is clicked while not active, requesting a scroll to be performed to bring it on-screen.
+            /// </summary>
             public Action<ColumnDimContainer>? RequestScroll { get; set; }
 
             [Resolved]
@@ -420,15 +588,20 @@ namespace osu.Game.Overlays.Mods
             protected override void LoadComplete()
             {
                 base.LoadComplete();
-                Active.BindValueChanged(_ => updateDim(), true);
+                Active.BindValueChanged(_ => updateState());
+                Column.AllFiltered.BindValueChanged(_ => updateState(), true);
                 FinishTransforms();
             }
 
-            private void updateDim()
+            protected override bool RequiresChildrenUpdate => base.RequiresChildrenUpdate || Column.SelectionAnimationRunning;
+
+            private void updateState()
             {
                 Colour4 targetColour;
 
-                if (Active.Value)
+                Column.Alpha = Column.AllFiltered.Value ? 0 : 1;
+
+                if (Column.Active.Value)
                     targetColour = Colour4.White;
                 else
                     targetColour = IsHovered ? colours.GrayC : colours.Gray8;
@@ -447,17 +620,20 @@ namespace osu.Game.Overlays.Mods
             protected override bool OnHover(HoverEvent e)
             {
                 base.OnHover(e);
-                updateDim();
+                updateState();
                 return Active.Value;
             }
 
             protected override void OnHoverLost(HoverLostEvent e)
             {
                 base.OnHoverLost(e);
-                updateDim();
+                updateState();
             }
         }
 
+        /// <summary>
+        /// A container which blocks and handles input, managing the "return from customisation" state change.
+        /// </summary>
         private class ClickToReturnContainer : Container
         {
             public BindableBool HandleMouse { get; } = new BindableBool();

osu.Game/Overlays/Mods/ModSettingsArea.cs

@@ -158,7 +158,7 @@ namespace osu.Game.Overlays.Mods
                         new[] { Empty() },
                         new Drawable[]
                         {
-                            new NestedVerticalScrollContainer
+                            new OsuScrollContainer(Direction.Vertical)
                             {
                                 RelativeSizeAxes = Axes.Both,
                                 ClampExtension = 100,

osu.Game/Overlays/Mods/NestedVerticalScrollContainer.cs

@@ -1,48 +0,0 @@
-// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
-// See the LICENCE file in the repository root for full licence text.
-
-#nullable enable
-
-using osu.Framework.Graphics;
-using osu.Framework.Input.Events;
-using osu.Game.Graphics.Containers;
-
-namespace osu.Game.Overlays.Mods
-{
-    /// <summary>
-    /// A scroll container that handles the case of vertically scrolling content inside a larger horizontally scrolling parent container.
-    /// </summary>
-    public class NestedVerticalScrollContainer : OsuScrollContainer
-    {
-        private ModSelectScreen.ColumnScrollContainer? parentScrollContainer;
-
-        protected override void LoadComplete()
-        {
-            base.LoadComplete();
-
-            parentScrollContainer = this.FindClosestParent<ModSelectScreen.ColumnScrollContainer>();
-        }
-
-        protected override bool OnScroll(ScrollEvent e)
-        {
-            if (parentScrollContainer == null)
-                return base.OnScroll(e);
-
-            bool topRightInView = parentScrollContainer.ScreenSpaceDrawQuad.Contains(ScreenSpaceDrawQuad.TopRight);
-            bool bottomLeftInView = parentScrollContainer.ScreenSpaceDrawQuad.Contains(ScreenSpaceDrawQuad.BottomLeft);
-
-            // If not completely on-screen, handle scroll but also allow parent to scroll at the same time (to hopefully bring our content into full view).
-            if (!topRightInView || !bottomLeftInView)
-                return false;
-
-            bool scrollingPastEnd = e.ScrollDelta.Y < 0 && IsScrolledToEnd();
-            bool scrollingPastStart = e.ScrollDelta.Y > 0 && Target <= 0;
-
-            // If at either of our extents, delegate scroll to the horizontal parent container.
-            if (scrollingPastStart || scrollingPastEnd)
-                return false;
-
-            return base.OnScroll(e);
-        }
-    }
-}

osu.Game/Overlays/Mods/ShearedOverlayContainer.cs

@@ -51,17 +51,15 @@ namespace osu.Game.Overlays.Mods
         /// </summary>
         protected Container FooterContent { get; private set; }
 
-        protected abstract OverlayColourScheme ColourScheme { get; }
-
         protected override bool StartHidden => true;
 
         protected override bool BlockNonPositionalInput => true;
 
-        protected ShearedOverlayContainer()
+        protected ShearedOverlayContainer(OverlayColourScheme colourScheme)
         {
             RelativeSizeAxes = Axes.Both;
 
-            ColourProvider = new OverlayColourProvider(ColourScheme);
+            ColourProvider = new OverlayColourProvider(colourScheme);
         }
 
         [BackgroundDependencyLoader]

osu.Game/Overlays/Mods/UserModSelectScreen.cs

@@ -12,6 +12,11 @@ namespace osu.Game.Overlays.Mods
 {
     public class UserModSelectScreen : ModSelectScreen
     {
+        public UserModSelectScreen(OverlayColourScheme colourScheme = OverlayColourScheme.Green)
+            : base(colourScheme)
+        {
+        }
+
         protected override ModColumn CreateModColumn(ModType modType, Key[] toggleKeys = null) => new UserModColumn(modType, false, toggleKeys);
 
         protected override IReadOnlyList<Mod> ComputeNewModsFromSelection(IReadOnlyList<Mod> oldSelection, IReadOnlyList<Mod> newSelection)

osu.Game/Overlays/Profile/Header/Components/LevelProgressBar.cs

@@ -62,7 +62,7 @@ namespace osu.Game.Overlays.Profile.Header.Components
         private void updateProgress(APIUser user)
         {
             levelProgressBar.Length = user?.Statistics?.Level.Progress / 100f ?? 0;
-            levelProgressText.Text = user?.Statistics?.Level.Progress.ToLocalisableString("0'%'") ?? default(LocalisableString);
+            levelProgressText.Text = user?.Statistics?.Level.Progress.ToLocalisableString("0'%'") ?? default;
         }
     }
 }

osu.Game/Overlays/Rankings/SpotlightSelector.cs

@@ -126,7 +126,7 @@ namespace osu.Game.Overlays.Rankings
             startDateColumn.Value = dateToString(response.Spotlight.StartDate);
             endDateColumn.Value = dateToString(response.Spotlight.EndDate);
             mapCountColumn.Value = response.BeatmapSets.Count.ToLocalisableString(@"N0");
-            participantsColumn.Value = response.Spotlight.Participants?.ToLocalisableString(@"N0") ?? default(LocalisableString);
+            participantsColumn.Value = response.Spotlight.Participants?.ToLocalisableString(@"N0") ?? default;
         }
 
         private LocalisableString dateToString(DateTimeOffset date) => date.ToLocalisableString(@"yyyy-MM-dd");

osu.Game/Overlays/Rankings/Tables/PerformanceTable.cs

@@ -5,7 +5,6 @@ using System.Collections.Generic;
 using osu.Framework.Extensions.LocalisationExtensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
-using osu.Framework.Localisation;
 using osu.Game.Resources.Localisation.Web;
 using osu.Game.Users;
 
@@ -25,7 +24,7 @@ namespace osu.Game.Overlays.Rankings.Tables
 
         protected override Drawable[] CreateUniqueContent(UserStatistics item) => new Drawable[]
         {
-            new RowText { Text = item.PP?.ToLocalisableString(@"N0") ?? default(LocalisableString), }
+            new RowText { Text = item.PP?.ToLocalisableString(@"N0") ?? default, }
         };
     }
 }

osu.Game/Rulesets/Mods/IMod.cs

@@ -39,6 +39,18 @@ namespace osu.Game.Rulesets.Mods
         /// </summary>
         bool UserPlayable { get; }
 
+        /// <summary>
+        /// Whether this mod is valid for multiplayer matches.
+        /// Should be <c>false</c> for mods that make gameplay duration dependent on user input (e.g. <see cref="ModAdaptiveSpeed"/>).
+        /// </summary>
+        bool ValidForMultiplayer { get; }
+
+        /// <summary>
+        /// Whether this mod is valid as a free mod in multiplayer matches.
+        /// Should be <c>false</c> for mods that affect the gameplay duration (e.g. <see cref="ModRateAdjust"/> and <see cref="ModTimeRamp"/>).
+        /// </summary>
+        bool ValidForMultiplayerAsFreeMod { get; }
+
         /// <summary>
         /// Create a fresh <see cref="Mod"/> instance based on this mod.
         /// </summary>

osu.Game/Rulesets/Mods/Mod.cs

@@ -94,6 +94,12 @@ namespace osu.Game.Rulesets.Mods
         [JsonIgnore]
         public virtual bool UserPlayable => true;
 
+        [JsonIgnore]
+        public virtual bool ValidForMultiplayer => true;
+
+        [JsonIgnore]
+        public virtual bool ValidForMultiplayerAsFreeMod => true;
+
         [Obsolete("Going forward, the concept of \"ranked\" doesn't exist. The only exceptions are automation mods, which should now override and set UserPlayable to false.")] // Can be removed 20211009
         public virtual bool Ranked => false;
 

osu.Game/Rulesets/Mods/ModAdaptiveSpeed.cs

@@ -31,6 +31,9 @@ namespace osu.Game.Rulesets.Mods
 
         public override double ScoreMultiplier => 1;
 
+        public override bool ValidForMultiplayer => false;
+        public override bool ValidForMultiplayerAsFreeMod => false;
+
         public override Type[] IncompatibleMods => new[] { typeof(ModRateAdjust), typeof(ModTimeRamp) };
 
         [SettingSource("Initial rate", "The starting speed of the track")]

osu.Game/Rulesets/Mods/ModAutoplay.cs

@@ -25,6 +25,8 @@ namespace osu.Game.Rulesets.Mods
         public bool RestartOnFail => false;
 
         public override bool UserPlayable => false;
+        public override bool ValidForMultiplayer => false;
+        public override bool ValidForMultiplayerAsFreeMod => false;
 
         public override Type[] IncompatibleMods => new[] { typeof(ModCinema), typeof(ModRelax), typeof(ModFailCondition), typeof(ModNoFail) };
 

osu.Game/Rulesets/Mods/ModRateAdjust.cs

@@ -11,6 +11,8 @@ namespace osu.Game.Rulesets.Mods
 {
     public abstract class ModRateAdjust : Mod, IApplicableToRate
     {
+        public override bool ValidForMultiplayerAsFreeMod => false;
+
         public abstract BindableNumber<double> SpeedChange { get; }
 
         public virtual void ApplyToTrack(ITrack track)

osu.Game/Rulesets/Mods/ModTimeRamp.cs

@@ -30,6 +30,8 @@ namespace osu.Game.Rulesets.Mods
         [SettingSource("Adjust pitch", "Should pitch be adjusted with speed")]
         public abstract BindableBool AdjustPitch { get; }
 
+        public override bool ValidForMultiplayerAsFreeMod => false;
+
         public override Type[] IncompatibleMods => new[] { typeof(ModRateAdjust), typeof(ModAdaptiveSpeed) };
 
         public override string SettingDescription => $"{InitialRate.Value:N2}x to {FinalRate.Value:N2}x";

osu.Game/Rulesets/Mods/UnknownMod.cs

@@ -16,6 +16,8 @@ namespace osu.Game.Rulesets.Mods
         public override double ScoreMultiplier => 0;
 
         public override bool UserPlayable => false;
+        public override bool ValidForMultiplayer => false;
+        public override bool ValidForMultiplayerAsFreeMod => false;
 
         public override ModType Type => ModType.System;
 

osu.Game/Screens/Edit/Compose/Components/CircularDistanceSnapGrid.cs

@@ -2,11 +2,15 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using osu.Framework.Allocation;
+using osu.Framework.Extensions.Color4Extensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Shapes;
 using osu.Framework.Graphics.UserInterface;
+using osu.Game.Rulesets.Edit;
 using osu.Game.Rulesets.Objects;
 using osuTK;
+using osuTK.Graphics;
 
 namespace osu.Game.Screens.Edit.Compose.Components
 {
@@ -51,14 +55,12 @@ namespace osu.Game.Screens.Edit.Compose.Components
             {
                 float diameter = (i + 1) * DistanceBetweenTicks * 2;
 
-                AddInternal(new CircularProgress
+                AddInternal(new Ring(ReferenceObject, GetColourForIndexFromPlacement(i))
                 {
-                    Origin = Anchor.Centre,
                     Position = StartPosition,
-                    Current = { Value = 1 },
+                    Origin = Anchor.Centre,
                     Size = new Vector2(diameter),
                     InnerRadius = 4 * 1f / diameter,
-                    Colour = GetColourForIndexFromPlacement(i)
                 });
             }
         }
@@ -100,5 +102,45 @@ namespace osu.Game.Screens.Edit.Compose.Components
 
             return (snappedPosition, snappedTime);
         }
+
+        private class Ring : CircularProgress
+        {
+            [Resolved]
+            private IDistanceSnapProvider snapProvider { get; set; }
+
+            [Resolved(canBeNull: true)]
+            private EditorClock editorClock { get; set; }
+
+            private readonly HitObject referenceObject;
+
+            private readonly Color4 baseColour;
+
+            public Ring(HitObject referenceObject, Color4 baseColour)
+            {
+                this.referenceObject = referenceObject;
+
+                Colour = this.baseColour = baseColour;
+
+                Current.Value = 1;
+            }
+
+            protected override void Update()
+            {
+                base.Update();
+
+                if (editorClock == null)
+                    return;
+
+                float distanceSpacingMultiplier = (float)snapProvider.DistanceSpacingMultiplier.Value;
+                double timeFromReferencePoint = editorClock.CurrentTime - referenceObject.GetEndTime();
+
+                float distanceForCurrentTime = snapProvider.DurationToDistance(referenceObject, timeFromReferencePoint)
+                                               * distanceSpacingMultiplier;
+
+                float timeBasedAlpha = 1 - Math.Clamp(Math.Abs(distanceForCurrentTime - Size.X / 2) / 30, 0, 1);
+
+                Colour = baseColour.Opacity(Math.Max(baseColour.A, timeBasedAlpha));
+            }
+        }
     }
 }

osu.Game/Screens/Edit/Compose/Components/DistanceSnapGrid.cs

@@ -4,14 +4,15 @@
 using System;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
+using osu.Framework.Extensions.Color4Extensions;
 using osu.Framework.Graphics;
-using osu.Framework.Graphics.Colour;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Layout;
 using osu.Game.Graphics;
 using osu.Game.Rulesets.Edit;
 using osu.Game.Rulesets.Objects;
 using osuTK;
+using osuTK.Graphics;
 
 namespace osu.Game.Screens.Edit.Compose.Components
 {
@@ -135,7 +136,7 @@ namespace osu.Game.Screens.Edit.Compose.Components
         /// </summary>
         /// <param name="placementIndex">The 0-based beat index from the point of placement.</param>
         /// <returns>The applicable colour.</returns>
-        protected ColourInfo GetColourForIndexFromPlacement(int placementIndex)
+        protected Color4 GetColourForIndexFromPlacement(int placementIndex)
         {
             var timingPoint = Beatmap.ControlPointInfo.TimingPointAt(StartTime);
             double beatLength = timingPoint.BeatLength / beatDivisor.Value;
@@ -144,7 +145,7 @@ namespace osu.Game.Screens.Edit.Compose.Components
             var colour = BindableBeatDivisor.GetColourFor(BindableBeatDivisor.GetDivisorForBeatIndex(beatIndex + placementIndex + 1, beatDivisor.Value), Colours);
 
             int repeatIndex = placementIndex / beatDivisor.Value;
-            return ColourInfo.SingleColour(colour).MultiplyAlpha(0.5f / (repeatIndex + 1));
+            return colour.Opacity(0.5f / (repeatIndex + 1));
         }
     }
 }

osu.Game/Screens/Edit/Compose/Components/SelectionBoxRotationHandle.cs

@@ -100,7 +100,7 @@ namespace osu.Game.Screens.Edit.Compose.Components
 
         private void updateTooltipText()
         {
-            TooltipText = cumulativeRotation.Value?.ToLocalisableString("0.0°") ?? default(LocalisableString);
+            TooltipText = cumulativeRotation.Value?.ToLocalisableString("0.0°") ?? default;
         }
     }
 }

osu.Game/Screens/Edit/Editor.cs

@@ -19,6 +19,7 @@ using osu.Framework.Input.Events;
 using osu.Framework.Logging;
 using osu.Framework.Platform;
 using osu.Framework.Screens;
+using osu.Game.Audio;
 using osu.Game.Beatmaps;
 using osu.Game.Configuration;
 using osu.Game.Database;
@@ -50,7 +51,6 @@ using osuTK.Input;
 namespace osu.Game.Screens.Edit
 {
     [Cached(typeof(IBeatSnapProvider))]
-    [Cached(typeof(ISamplePlaybackDisabler))]
     [Cached]
     public class Editor : ScreenWithBeatmapBackground, IKeyBindingHandler<GlobalAction>, IKeyBindingHandler<PlatformAction>, IBeatSnapProvider, ISamplePlaybackDisabler
     {

osu.Game/Screens/OnlinePlay/Components/DrawableGameType.cs

@@ -87,44 +87,46 @@ namespace osu.Game.Screens.OnlinePlay.Components
                         },
                     };
 
-                // case MatchType.TagCoop:
-                //     return new SpriteIcon
-                //     {
-                //         Anchor = Anchor.Centre,
-                //         Origin = Anchor.Centre,
-                //         Size = new Vector2(size),
-                //         Icon = FontAwesome.Solid.Sync,
-                //         Colour = colours.Blue,
-                //
-                //         Shadow = false
-                //     };
+#pragma warning disable IDE0055 // Indentation of commented code
+                    // case MatchType.TagCoop:
+                    //     return new SpriteIcon
+                    //     {
+                    //         Anchor = Anchor.Centre,
+                    //         Origin = Anchor.Centre,
+                    //         Size = new Vector2(size),
+                    //         Icon = FontAwesome.Solid.Sync,
+                    //         Colour = colours.Blue,
+                    //
+                    //         Shadow = false
+                    //     };
 
-                // case MatchType.TagTeamCoop:
-                //     return new FillFlowContainer
-                //     {
-                //         Anchor = Anchor.Centre,
-                //         Origin = Anchor.Centre,
-                //         AutoSizeAxes = Axes.Both,
-                //         Direction = FillDirection.Horizontal,
-                //         Spacing = new Vector2(2f),
-                //         Children = new[]
-                //         {
-                //             new SpriteIcon
-                //             {
-                //                 Icon = FontAwesome.Solid.Sync,
-                //                 Size = new Vector2(size * 0.75f),
-                //                 Colour = colours.Blue,
-                //                 Shadow = false,
-                //             },
-                //             new SpriteIcon
-                //             {
-                //                 Icon = FontAwesome.Solid.Sync,
-                //                 Size = new Vector2(size * 0.75f),
-                //                 Colour = colours.Pink,
-                //                 Shadow = false,
-                //             },
-                //         },
-                //     };
+                    // case MatchType.TagTeamCoop:
+                    //     return new FillFlowContainer
+                    //     {
+                    //         Anchor = Anchor.Centre,
+                    //         Origin = Anchor.Centre,
+                    //         AutoSizeAxes = Axes.Both,
+                    //         Direction = FillDirection.Horizontal,
+                    //         Spacing = new Vector2(2f),
+                    //         Children = new[]
+                    //         {
+                    //             new SpriteIcon
+                    //             {
+                    //                 Icon = FontAwesome.Solid.Sync,
+                    //                 Size = new Vector2(size * 0.75f),
+                    //                 Colour = colours.Blue,
+                    //                 Shadow = false,
+                    //             },
+                    //             new SpriteIcon
+                    //             {
+                    //                 Icon = FontAwesome.Solid.Sync,
+                    //                 Size = new Vector2(size * 0.75f),
+                    //                 Colour = colours.Pink,
+                    //                 Shadow = false,
+                    //             },
+                    //         },
+                    //     };
+#pragma warning restore IDE0055
             }
         }
 

osu.Game/Screens/OnlinePlay/FreeModSelectScreen.cs

@@ -2,15 +2,19 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using osu.Game.Overlays;
+using System.Collections.Generic;
+using osu.Framework.Graphics;
+using osu.Game.Graphics.UserInterface;
 using osu.Game.Overlays.Mods;
 using osu.Game.Rulesets.Mods;
 using osuTK.Input;
+using osu.Game.Localisation;
 
 namespace osu.Game.Screens.OnlinePlay
 {
     public class FreeModSelectScreen : ModSelectScreen
     {
-        protected override bool AllowCustomisation => false;
         protected override bool ShowTotalMultiplier => false;
 
         public new Func<Mod, bool> IsValidMod
@@ -20,10 +24,29 @@ namespace osu.Game.Screens.OnlinePlay
         }
 
         public FreeModSelectScreen()
+            : base(OverlayColourScheme.Plum)
         {
             IsValidMod = _ => true;
         }
 
         protected override ModColumn CreateModColumn(ModType modType, Key[] toggleKeys = null) => new ModColumn(modType, true, toggleKeys);
+
+        protected override IEnumerable<ShearedButton> CreateFooterButtons() => new[]
+        {
+            new ShearedButton(BUTTON_WIDTH)
+            {
+                Anchor = Anchor.BottomLeft,
+                Origin = Anchor.BottomLeft,
+                Text = CommonStrings.SelectAll,
+                Action = SelectAll
+            },
+            new ShearedButton(BUTTON_WIDTH)
+            {
+                Anchor = Anchor.BottomLeft,
+                Origin = Anchor.BottomLeft,
+                Text = CommonStrings.DeselectAll,
+                Action = DeselectAll
+            }
+        };
     }
 }

osu.Game/Screens/OnlinePlay/Match/RoomSubScreen.cs

@@ -5,6 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
+using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Audio;
 using osu.Framework.Audio.Sample;
@@ -57,6 +58,9 @@ namespace osu.Game.Screens.OnlinePlay.Match
 
         protected readonly IBindable<long?> RoomId = new Bindable<long?>();
 
+        [Resolved(CanBeNull = true)]
+        private IOverlayManager overlayManager { get; set; }
+
         [Resolved]
         private MusicController music { get; set; }
 
@@ -77,7 +81,11 @@ namespace osu.Game.Screens.OnlinePlay.Match
         public readonly Room Room;
         private readonly bool allowEdit;
 
-        private ModSelectOverlay userModsSelectOverlay;
+        private ModSelectScreen userModsSelectOverlay;
+
+        [CanBeNull]
+        private IDisposable userModsSelectOverlayRegistration;
+
         private RoomSettingsOverlay settingsOverlay;
         private Drawable mainContent;
 
@@ -180,11 +188,6 @@ namespace osu.Game.Screens.OnlinePlay.Match
                                                                 Origin = Anchor.BottomLeft,
                                                                 RelativeSizeAxes = Axes.X,
                                                                 AutoSizeAxes = Axes.Y,
-                                                                Child = userModsSelectOverlay = new UserModSelectOverlay
-                                                                {
-                                                                    SelectedMods = { BindTarget = UserMods },
-                                                                    IsValidMod = _ => false
-                                                                }
                                                             },
                                                         }
                                                     }
@@ -227,6 +230,12 @@ namespace osu.Game.Screens.OnlinePlay.Match
                     }
                 }
             };
+
+            LoadComponent(userModsSelectOverlay = new UserModSelectScreen(OverlayColourScheme.Plum)
+            {
+                SelectedMods = { BindTarget = UserMods },
+                IsValidMod = _ => false
+            });
         }
 
         protected override void LoadComplete()
@@ -254,6 +263,8 @@ namespace osu.Game.Screens.OnlinePlay.Match
 
             beatmapAvailabilityTracker.SelectedItem.BindTo(SelectedItem);
             beatmapAvailabilityTracker.Availability.BindValueChanged(_ => updateWorkingBeatmap());
+
+            userModsSelectOverlayRegistration = overlayManager?.RegisterBlockingOverlay(userModsSelectOverlay);
         }
 
         protected override IReadOnlyDependencyContainer CreateChildDependencies(IReadOnlyDependencyContainer parent)
@@ -298,7 +309,7 @@ namespace osu.Game.Screens.OnlinePlay.Match
 
         public override void OnSuspending(ScreenTransitionEvent e)
         {
-            endHandlingTrack();
+            onLeaving();
             base.OnSuspending(e);
         }
 
@@ -316,7 +327,7 @@ namespace osu.Game.Screens.OnlinePlay.Match
             RoomManager?.PartRoom();
             Mods.Value = Array.Empty<Mod>();
 
-            endHandlingTrack();
+            onLeaving();
 
             return base.OnExiting(e);
         }
@@ -412,6 +423,12 @@ namespace osu.Game.Screens.OnlinePlay.Match
             Beatmap.BindValueChanged(applyLoopingToTrack, true);
         }
 
+        private void onLeaving()
+        {
+            userModsSelectOverlay.Hide();
+            endHandlingTrack();
+        }
+
         private void endHandlingTrack()
         {
             Beatmap.ValueChanged -= applyLoopingToTrack;
@@ -459,5 +476,12 @@ namespace osu.Game.Screens.OnlinePlay.Match
         public class UserModSelectButton : PurpleTriangleButton
         {
         }
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+
+            userModsSelectOverlayRegistration?.Dispose();
+        }
     }
 }

osu.Game/Screens/OnlinePlay/Multiplayer/MultiplayerMatchSongSelect.cs

@@ -95,6 +95,8 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer
 
         protected override BeatmapDetailArea CreateBeatmapDetailArea() => new PlayBeatmapDetailArea();
 
-        protected override bool IsValidFreeMod(Mod mod) => base.IsValidFreeMod(mod) && !(mod is ModTimeRamp) && !(mod is ModRateAdjust);
+        protected override bool IsValidMod(Mod mod) => base.IsValidMod(mod) && mod.ValidForMultiplayer;
+
+        protected override bool IsValidFreeMod(Mod mod) => base.IsValidFreeMod(mod) && mod.ValidForMultiplayerAsFreeMod;
     }
 }

osu.Game/Screens/OnlinePlay/OnlinePlaySongSelect.cs

@@ -14,6 +14,7 @@ using osu.Framework.Screens;
 using osu.Game.Beatmaps;
 using osu.Game.Online.API;
 using osu.Game.Online.Rooms;
+using osu.Game.Overlays;
 using osu.Game.Overlays.Mods;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Mods;
@@ -45,7 +46,6 @@ namespace osu.Game.Screens.OnlinePlay
 
         protected readonly Bindable<IReadOnlyList<Mod>> FreeMods = new Bindable<IReadOnlyList<Mod>>(Array.Empty<Mod>());
 
-        private readonly FreeModSelectOverlay freeModSelectOverlay;
         private readonly Room room;
 
         private WorkingBeatmap initialBeatmap;
@@ -53,13 +53,16 @@ namespace osu.Game.Screens.OnlinePlay
         private IReadOnlyList<Mod> initialMods;
         private bool itemSelected;
 
+        private readonly FreeModSelectScreen freeModSelectOverlay;
+        private IDisposable freeModSelectOverlayRegistration;
+
         protected OnlinePlaySongSelect(Room room)
         {
             this.room = room;
 
             Padding = new MarginPadding { Horizontal = HORIZONTAL_OVERFLOW_PADDING };
 
-            freeModSelectOverlay = new FreeModSelectOverlay
+            freeModSelectOverlay = new FreeModSelectScreen
             {
                 SelectedMods = { BindTarget = FreeMods },
                 IsValidMod = IsValidFreeMod,
@@ -75,7 +78,7 @@ namespace osu.Game.Screens.OnlinePlay
             initialRuleset = Ruleset.Value;
             initialMods = Mods.Value.ToList();
 
-            FooterPanels.Add(freeModSelectOverlay);
+            LoadComponent(freeModSelectOverlay);
         }
 
         protected override void LoadComplete()
@@ -94,6 +97,8 @@ namespace osu.Game.Screens.OnlinePlay
 
             Mods.BindValueChanged(onModsChanged);
             Ruleset.BindValueChanged(onRulesetChanged);
+
+            freeModSelectOverlayRegistration = OverlayManager?.RegisterBlockingOverlay(freeModSelectOverlay);
         }
 
         private void onModsChanged(ValueChangedEvent<IReadOnlyList<Mod>> mods)
@@ -150,10 +155,12 @@ namespace osu.Game.Screens.OnlinePlay
                 Mods.Value = initialMods;
             }
 
+            freeModSelectOverlay.Hide();
+
             return base.OnExiting(e);
         }
 
-        protected override ModSelectOverlay CreateModSelectOverlay() => new UserModSelectOverlay
+        protected override ModSelectScreen CreateModSelectOverlay() => new UserModSelectScreen(OverlayColourScheme.Plum)
         {
             IsValidMod = IsValidMod
         };
@@ -182,5 +189,12 @@ namespace osu.Game.Screens.OnlinePlay
         private bool checkCompatibleFreeMod(Mod mod)
             => Mods.Value.All(m => m.Acronym != mod.Acronym) // Mod must not be contained in the required mods.
                && ModUtils.CheckCompatibleSet(Mods.Value.Append(mod).ToArray()); // Mod must be compatible with all the required mods.
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+
+            freeModSelectOverlayRegistration?.Dispose();
+        }
     }
 }

osu.Game/Screens/Play/Player.cs

@@ -16,6 +16,7 @@ using osu.Framework.Input.Events;
 using osu.Framework.Logging;
 using osu.Framework.Screens;
 using osu.Framework.Threading;
+using osu.Game.Audio;
 using osu.Game.Beatmaps;
 using osu.Game.Configuration;
 using osu.Game.Graphics.Containers;
@@ -37,7 +38,6 @@ using osuTK.Graphics;
 namespace osu.Game.Screens.Play
 {
     [Cached]
-    [Cached(typeof(ISamplePlaybackDisabler))]
     public abstract class Player : ScreenWithBeatmapBackground, ISamplePlaybackDisabler, ILocalUserPlayInfo
     {
         /// <summary>

osu.Game/Screens/Ranking/ScorePanelList.cs

@@ -85,7 +85,6 @@ namespace osu.Game.Screens.Ranking
             InternalChild = scroll = new Scroll
             {
                 RelativeSizeAxes = Axes.Both,
-                HandleScroll = () => expandedPanel?.IsHovered != true, // handle horizontal scroll only when not hovering the expanded panel.
                 Child = flow = new Flow
                 {
                     Anchor = Anchor.Centre,
@@ -359,11 +358,6 @@ namespace osu.Game.Screens.Ranking
             /// </summary>
             public float? InstantScrollTarget;
 
-            /// <summary>
-            /// Whether this container should handle scroll trigger events.
-            /// </summary>
-            public Func<bool> HandleScroll;
-
             protected override void UpdateAfterChildren()
             {
                 if (InstantScrollTarget != null)
@@ -374,10 +368,6 @@ namespace osu.Game.Screens.Ranking
 
                 base.UpdateAfterChildren();
             }
-
-            public override bool HandlePositionalInput => HandleScroll();
-
-            public override bool HandleNonPositionalInput => HandleScroll();
         }
     }
 }

osu.Game/Screens/Select/SongSelect.cs

@@ -35,6 +35,7 @@ using osu.Framework.Input.Bindings;
 using osu.Game.Collections;
 using osu.Game.Graphics.UserInterface;
 using System.Diagnostics;
+using JetBrains.Annotations;
 using osu.Game.Screens.Play;
 using osu.Game.Database;
 using osu.Game.Skinning;
@@ -101,7 +102,7 @@ namespace osu.Game.Screens.Select
         [Resolved(CanBeNull = true)]
         private LegacyImportManager legacyImportManager { get; set; }
 
-        protected ModSelectOverlay ModSelect { get; private set; }
+        protected ModSelectScreen ModSelect { get; private set; }
 
         protected Sample SampleConfirm { get; private set; }
 
@@ -116,9 +117,15 @@ namespace osu.Game.Screens.Select
 
         private double audioFeedbackLastPlaybackTime;
 
+        [CanBeNull]
+        private IDisposable modSelectOverlayRegistration;
+
         [Resolved]
         private MusicController music { get; set; }
 
+        [Resolved(CanBeNull = true)]
+        internal IOverlayManager OverlayManager { get; private set; }
+
         [BackgroundDependencyLoader(true)]
         private void load(AudioManager audio, IDialogOverlay dialog, OsuColour colours, ManageCollectionsDialog manageCollectionsDialog, DifficultyRecommender recommender)
         {
@@ -252,38 +259,25 @@ namespace osu.Game.Screens.Select
             {
                 AddRangeInternal(new Drawable[]
                 {
-                    new GridContainer // used for max height implementation
+                    FooterPanels = new Container
                     {
+                        Anchor = Anchor.BottomLeft,
+                        Origin = Anchor.BottomLeft,
                         RelativeSizeAxes = Axes.Both,
-                        RowDimensions = new[]
+                        Padding = new MarginPadding { Bottom = Footer.HEIGHT },
+                        Children = new Drawable[]
                         {
-                            new Dimension(),
-                            new Dimension(GridSizeMode.Relative, 1f, maxSize: ModSelectOverlay.HEIGHT + Footer.HEIGHT),
-                        },
-                        Content = new[]
-                        {
-                            null,
-                            new Drawable[]
-                            {
-                                FooterPanels = new Container
-                                {
-                                    Anchor = Anchor.BottomLeft,
-                                    Origin = Anchor.BottomLeft,
-                                    RelativeSizeAxes = Axes.Both,
-                                    Padding = new MarginPadding { Bottom = Footer.HEIGHT },
-                                    Children = new Drawable[]
-                                    {
-                                        BeatmapOptions = new BeatmapOptionsOverlay(),
-                                        ModSelect = CreateModSelectOverlay()
-                                    }
-                                }
-                            }
+                            BeatmapOptions = new BeatmapOptionsOverlay(),
                         }
                     },
-                    Footer = new Footer()
+                    Footer = new Footer(),
                 });
             }
 
+            // preload the mod select overlay for later use in `LoadComplete()`.
+            // therein it will be registered at the `OsuGame` level to properly function as a blocking overlay.
+            LoadComponent(ModSelect = CreateModSelectOverlay());
+
             if (Footer != null)
             {
                 foreach (var (button, overlay) in CreateFooterButtons())
@@ -317,6 +311,13 @@ namespace osu.Game.Screens.Select
             }
         }
 
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            modSelectOverlayRegistration = OverlayManager?.RegisterBlockingOverlay(ModSelect);
+        }
+
         /// <summary>
         /// Creates the buttons to be displayed in the footer.
         /// </summary>
@@ -332,7 +333,7 @@ namespace osu.Game.Screens.Select
             (new FooterButtonOptions(), BeatmapOptions)
         };
 
-        protected virtual ModSelectOverlay CreateModSelectOverlay() => new UserModSelectOverlay();
+        protected virtual ModSelectScreen CreateModSelectOverlay() => new UserModSelectScreen();
 
         protected virtual void ApplyFilterToCarousel(FilterCriteria criteria)
         {
@@ -658,6 +659,7 @@ namespace osu.Game.Screens.Select
                 return true;
 
             beatmapInfoWedge.Hide();
+            ModSelect.Hide();
 
             this.FadeOut(100);
 
@@ -716,6 +718,8 @@ namespace osu.Game.Screens.Select
 
             if (music != null)
                 music.TrackChanged -= ensureTrackLooping;
+
+            modSelectOverlayRegistration?.Dispose();
         }
 
         /// <summary>

osu.Game/Skinning/PausableSkinnableSound.cs

@@ -8,7 +8,6 @@ using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Threading;
 using osu.Game.Audio;
-using osu.Game.Screens.Play;
 
 namespace osu.Game.Skinning
 {

osu.Game/Tests/Visual/ScreenTestScene.cs

@@ -1,12 +1,15 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using osu.Framework.Allocation;
+using osu.Framework.Bindables;
 using osu.Framework.Development;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Logging;
 using osu.Framework.Testing;
+using osu.Game.Graphics;
 using osu.Game.Overlays;
 using osu.Game.Screens;
 
@@ -15,11 +18,12 @@ namespace osu.Game.Tests.Visual
     /// <summary>
     /// A test case which can be used to test a screen (that relies on OnEntering being called to execute startup instructions).
     /// </summary>
-    public abstract class ScreenTestScene : OsuManualInputManagerTestScene
+    public abstract class ScreenTestScene : OsuManualInputManagerTestScene, IOverlayManager
     {
         protected readonly OsuScreenStack Stack;
 
         private readonly Container content;
+        private readonly Container overlayContent;
 
         protected override Container<Drawable> Content => content;
 
@@ -36,7 +40,11 @@ namespace osu.Game.Tests.Visual
                     RelativeSizeAxes = Axes.Both
                 },
                 content = new Container { RelativeSizeAxes = Axes.Both },
-                DialogOverlay = new DialogOverlay()
+                overlayContent = new Container
+                {
+                    RelativeSizeAxes = Axes.Both,
+                    Child = DialogOverlay = new DialogOverlay()
+                }
             });
 
             Stack.ScreenPushed += (lastScreen, newScreen) => Logger.Log($"{nameof(ScreenTestScene)} screen changed → {newScreen}");
@@ -65,5 +73,26 @@ namespace osu.Game.Tests.Visual
                 return false;
             });
         }
+
+        #region IOverlayManager
+
+        IBindable<OverlayActivation> IOverlayManager.OverlayActivationMode { get; } = new Bindable<OverlayActivation>(OverlayActivation.All);
+
+        // in the blocking methods below it is important to be careful about threading (e.g. use `Expire()` rather than `Remove()`, and schedule transforms),
+        // because in the worst case the clean-up methods could be called from async disposal.
+
+        IDisposable IOverlayManager.RegisterBlockingOverlay(OverlayContainer overlayContainer)
+        {
+            overlayContent.Add(overlayContainer);
+            return new InvokeOnDisposal(() => overlayContainer.Expire());
+        }
+
+        void IOverlayManager.ShowBlockingOverlay(OverlayContainer overlay)
+            => Schedule(() => Stack.FadeColour(OsuColour.Gray(0.5f), 500, Easing.OutQuint));
+
+        void IOverlayManager.HideBlockingOverlay(OverlayContainer overlay)
+            => Schedule(() => Stack.FadeColour(Colour4.White, 500, Easing.OutQuint));
+
+        #endregion
     }
 }

osu.Game/Utils/ModUtils.cs

@@ -106,22 +106,69 @@ namespace osu.Game.Utils
         }
 
         /// <summary>
-        /// Check the provided combination of mods are valid for a local gameplay session.
+        /// Checks that all <see cref="Mod"/>s in a combination are valid for a local gameplay session.
         /// </summary>
         /// <param name="mods">The mods to check.</param>
-        /// <param name="invalidMods">Invalid mods, if any were found. Can be null if all mods were valid.</param>
+        /// <param name="invalidMods">Invalid mods, if any were found. Will be null if all mods were valid.</param>
         /// <returns>Whether the input mods were all valid. If false, <paramref name="invalidMods"/> will contain all invalid entries.</returns>
         public static bool CheckValidForGameplay(IEnumerable<Mod> mods, [NotNullWhen(false)] out List<Mod>? invalidMods)
         {
             mods = mods.ToArray();
 
-            // exclude multi mods from compatibility checks.
-            // the loop below automatically marks all multi mods as not valid for gameplay anyway.
-            CheckCompatibleSet(mods.Where(m => !(m is MultiMod)), out invalidMods);
+            // checking compatibility of multi mods would try to flatten them and return incompatible mods.
+            // in gameplay context, we never want MultiMod selected in the first place, therefore check against it first.
+            if (!checkValid(mods, m => !(m is MultiMod), out invalidMods))
+                return false;
+
+            if (!CheckCompatibleSet(mods, out invalidMods))
+                return false;
+
+            return checkValid(mods, m => m.Type != ModType.System && m.HasImplementation, out invalidMods);
+        }
+
+        /// <summary>
+        /// Checks that all <see cref="Mod"/>s in a combination are valid as "required mods" in a multiplayer match session.
+        /// </summary>
+        /// <param name="mods">The mods to check.</param>
+        /// <param name="invalidMods">Invalid mods, if any were found. Will be null if all mods were valid.</param>
+        /// <returns>Whether the input mods were all valid. If false, <paramref name="invalidMods"/> will contain all invalid entries.</returns>
+        public static bool CheckValidRequiredModsForMultiplayer(IEnumerable<Mod> mods, [NotNullWhen(false)] out List<Mod>? invalidMods)
+        {
+            mods = mods.ToArray();
+
+            // checking compatibility of multi mods would try to flatten them and return incompatible mods.
+            // in gameplay context, we never want MultiMod selected in the first place, therefore check against it first.
+            if (!checkValid(mods, m => !(m is MultiMod), out invalidMods))
+                return false;
+
+            if (!CheckCompatibleSet(mods, out invalidMods))
+                return false;
+
+            return checkValid(mods, m => m.Type != ModType.System && m.HasImplementation && m.ValidForMultiplayer, out invalidMods);
+        }
+
+        /// <summary>
+        /// Checks that all <see cref="Mod"/>s in a combination are valid as "free mods" in a multiplayer match session.
+        /// </summary>
+        /// <remarks>
+        /// Note that this does not check compatibility between mods,
+        /// given that the passed mods are expected to be the ones to be allowed for the multiplayer match,
+        /// not to be confused with the list of mods the user currently has selected for the multiplayer match.
+        /// </remarks>
+        /// <param name="mods">The mods to check.</param>
+        /// <param name="invalidMods">Invalid mods, if any were found. Will be null if all mods were valid.</param>
+        /// <returns>Whether the input mods were all valid. If false, <paramref name="invalidMods"/> will contain all invalid entries.</returns>
+        public static bool CheckValidFreeModsForMultiplayer(IEnumerable<Mod> mods, [NotNullWhen(false)] out List<Mod>? invalidMods)
+            => checkValid(mods, m => m.Type != ModType.System && m.HasImplementation && m.ValidForMultiplayerAsFreeMod && !(m is MultiMod), out invalidMods);
+
+        private static bool checkValid(IEnumerable<Mod> mods, Predicate<Mod> valid, [NotNullWhen(false)] out List<Mod>? invalidMods)
+        {
+            mods = mods.ToArray();
+            invalidMods = null;
 
             foreach (var mod in mods)
             {
-                if (mod.Type == ModType.System || !mod.HasImplementation || mod is MultiMod)
+                if (!valid(mod))
                 {
                     invalidMods ??= new List<Mod>();
                     invalidMods.Add(mod);