im not exactly sure if this is an issue with Additional Additions, but its the only lead i have. this issue is one that has me completely clueless. me and my brother are making a mod pack that includes this mod, and his game runs just fine. he can create new single player worlds without issue. however when i click create new world, it tries to load the menu, says "saving world" and then crashes. both our mod lists are identical, no differences whatsoever even in configs. the only reason i had any clue to come here was because additional additions was the only mod mentioned in the crash report.

crash-2024-02-03_17.14.33-client.txt

(im not entirely sure how to send the crash report, but hopefully this works)

my best guess is something is abnormal in my .minecraft folder, just not sure what exactly would even conflict or cause this issue.