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This fell out while investigating why the issue with online IDs mismatching in the `.osu` could be worked around by importing the map three times in total when starting from it not being available locally. Here follows an explanation of why that "helped". Import 1: - The beatmap set is imported normally. - Online metadata population sees the online ID mismatch and resets it on the problematic beatmap. Import 2: - The existing beatmap set is found, but deemed not reusable because of the single beatmap having its ID reset to -1. - The existing beatmap set is marked deleted, and all the IDs of its beatmaps are reset to -1. - The beatmap set is reimported afresh. - Online metadata population still sees the online ID mismatch and resets it on the problematic beatmap. Note that at this point the first import *is still physically present in the database* but marked deleted. Import 3: - When trying to find the existing beatmap set to see if it can be reused, *the one pending deletion and with its IDs reset - - the remnant from import 1 - is returned*. - Because of this, `validateOnlineIds()` resets online IDs *on the model representing the current reimport*. - The beatmap set is reimported yet again. - With the online ID reset, the online metadata population check for online ID mismatch does not run because *the IDs were reset to -1* earlier. Preferring undeleted models when picking the model instance for reuse prevents this scenario.