In reply to amelbeabk:
I do not know but I recommend avoiding FTB for a few days.
You can get this free on curseforge for fabric, but forge could definitely use one.
In reply to deadmannil:
This issue is a mixin issue or sponge. Mods: modupdater, multiconnect, updatefixerupper. One of those should fix it.
common issue, modpacks arent working, and until they fix that, the issues of plenty will continue.
Ways to add mods of different versions without compatibility issues (currently can only use mods from 1.15.2
Ways to have big list of mods without crashing (50 to 100)
Having official modpack that stays up to date.
Issue with infinite loop on "Joining world"