Bug Report

What's the issue you encountered?

Currently, Biomes O' Plenty adds biome dictionary tags during FMLCommonSetupEvent. While this works, its making things difficult for mod compatibility as there is no event after FMLCommonSetupEvent that mods are supposed to use (only a Forge internal event and then server starting events). It would be a lot easier to just register them at the end of the RegistryEvent.Register<Biome> event, as nothing delays the tag registration.

One specific effect of this issue is with my mod SimplyTea. At best case, it means randomly my tree feature will not be added to Biomes' O Plenty forest biomes. At worst, it leads to a ConcurrentModificationException as seen in KnightMiner/SimplyTea#14.

Mod Version

Issue on my side was reported using 1.14.4-9.0.0.253. The crash specifically appears to be based on the number of threads available to loading, but the compatibility issue exists even without the crash.