Atmosfera

• [1.21.4] add null check for music, fixing a potential crash
• fix a bunch of concurrency issues, including a rare ConcurrentModificationException crash when playing sound
• replace thread pool of 4+ threads with two dedicated single-thread pools that discard old update tasks

port to 1.21.4

remove unneeded EntityMixin causing compatibility issues

port to 1.21.3

reupload from CurseForge

port to 1.21

port to 1.20 (backwards compatible with 1.19.3)

port to 1.19

port to 1.18.2