Use compound assignment.

.editorconfig

@@ -140,7 +140,7 @@ dotnet_style_prefer_inferred_anonymous_type_member_names = true:warning
 dotnet_style_prefer_auto_properties = true:warning
 dotnet_style_prefer_conditional_expression_over_assignment = true:silent
 dotnet_style_prefer_conditional_expression_over_return = true:silent
-dotnet_style_prefer_compound_assignment = true:silent
+dotnet_style_prefer_compound_assignment = true:warning
 
 #Style - null/type checks
 dotnet_style_coalesce_expression = true:warning

osu.Game.Rulesets.Catch/UI/CatcherArea.cs

@@ -198,7 +198,7 @@ namespace osu.Game.Rulesets.Catch.UI
                 var additive = createCatcherSprite();
 
                 additive.Anchor = Anchor;
-                additive.OriginPosition = additive.OriginPosition + new Vector2(DrawWidth / 2, 0); // also temporary to align sprite correctly.
+                additive.OriginPosition += new Vector2(DrawWidth / 2, 0); // also temporary to align sprite correctly.
                 additive.Position = Position;
                 additive.Scale = Scale;
                 additive.Colour = HyperDashing ? Color4.Red : Color4.White;

osu.Game.Rulesets.Mania/Beatmaps/ManiaBeatmapConverter.cs

@@ -51,7 +51,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
 
                 if (TargetColumns >= 10)
                 {
-                    TargetColumns = TargetColumns / 2;
+                    TargetColumns /= 2;
                     Dual = true;
                 }
             }

osu.Game.Rulesets.Mania/Edit/ManiaSelectionHandler.cs

@@ -55,7 +55,7 @@ namespace osu.Game.Rulesets.Mania.Edit
 
             // Flip the vertical coordinate space when scrolling downwards
             if (scrollingInfo.Direction.Value == ScrollingDirection.Down)
-                targetPosition = targetPosition - referenceParent.DrawHeight;
+                targetPosition -= referenceParent.DrawHeight;
 
             float movementDelta = targetPosition - reference.DrawableObject.Position.Y;
 

osu.Game.Rulesets.Mania/UI/ManiaPlayfield.cs

@@ -96,7 +96,7 @@ namespace osu.Game.Rulesets.Mania.UI
 
             foreach (var stage in stages)
             {
-                sum = sum + stage.Columns.Count;
+                sum += stage.Columns.Count;
                 if (sum > column)
                     return stage;
             }

osu.Game.Rulesets.Osu/Difficulty/Preprocessing/OsuDifficultyHitObject.cs

@@ -103,7 +103,7 @@ namespace osu.Game.Rulesets.Osu.Difficulty.Preprocessing
                 if (progress % 2 >= 1)
                     progress = 1 - progress % 1;
                 else
-                    progress = progress % 1;
+                    progress %= 1;
 
                 // ReSharper disable once PossibleInvalidOperationException (bugged in current r# version)
                 var diff = slider.StackedPosition + slider.Path.PositionAt(progress) - slider.LazyEndPosition.Value;

osu.Game.Rulesets.Osu/Edit/Blueprints/Sliders/Components/PathControlPointVisualiser.cs

@@ -114,7 +114,7 @@ namespace osu.Game.Rulesets.Osu.Edit.Blueprints.Sliders.Components
                         newControlPoints[i] = newControlPoints[i] - first;
 
                     // The slider's position defines the position of the first control point, and all further control points are relative to that point
-                    slider.Position = slider.Position + first;
+                    slider.Position += first;
 
                     // Since pieces are re-used, they will not point to the deleted control points while remaining selected
                     foreach (var piece in Pieces)

osu.Game.Tournament/Screens/Ladder/LadderDragContainer.cs

@@ -34,7 +34,7 @@ namespace osu.Game.Tournament.Screens.Ladder
         {
             var newScale = MathHelper.Clamp(scale + e.ScrollDelta.Y / 15 * scale, min_scale, max_scale);
 
-            this.MoveTo(target = target - e.MousePosition * (newScale - scale), 2000, Easing.OutQuint);
+            this.MoveTo(target -= e.MousePosition * (newScale - scale), 2000, Easing.OutQuint);
             this.ScaleTo(scale = newScale, 2000, Easing.OutQuint);
 
             return true;

osu.Game/Graphics/UserInterface/PercentageCounter.cs

@@ -41,7 +41,7 @@ namespace osu.Game.Graphics.UserInterface
 
         public override void Increment(double amount)
         {
-            Current.Value = Current.Value + amount;
+            Current.Value += amount;
         }
     }
 }

osu.Game/Graphics/UserInterface/ScoreCounter.cs

@@ -55,7 +55,7 @@ namespace osu.Game.Graphics.UserInterface
 
         public override void Increment(double amount)
         {
-            Current.Value = Current.Value + amount;
+            Current.Value += amount;
         }
     }
 }

osu.Game/Graphics/UserInterface/SimpleComboCounter.cs

@@ -33,7 +33,7 @@ namespace osu.Game.Graphics.UserInterface
 
         public override void Increment(int amount)
         {
-            Current.Value = Current.Value + amount;
+            Current.Value += amount;
         }
     }
 }

osu.Game/Screens/Play/HUD/ComboCounter.cs

@@ -114,7 +114,7 @@ namespace osu.Game.Screens.Play.HUD
         /// <param name="amount"></param>
         public void Increment(int amount = 1)
         {
-            Current.Value = Current.Value + amount;
+            Current.Value += amount;
         }
 
         /// <summary>

osu.Game/Screens/Play/HUD/ComboResultCounter.cs

@@ -26,7 +26,7 @@ namespace osu.Game.Screens.Play.HUD
 
         public override void Increment(long amount)
         {
-            Current.Value = Current.Value + amount;
+            Current.Value += amount;
         }
     }
 }