This is the crash log I got and I could not track it down to exactly which mods were interacting funny.

crash-2019-11-02_09.37.30-client.txt

This is the modlist -

• Autofish 0.8.4
• Chunkborders 0.4.1
• I am Very Smart 1.5.0+1.14.4
• Item sorter 0.15.0-dev.20190806.191755
• Light Overlay 3.6.1
• litematica 0.0.0-dev.20191018.224806
• MaLiLib 0.10.0-dev
• mamiyaotaru folder
• MiniHud 0.19.0-dev.20191007.003640
• Mod Menu 1.7.10+build.119 for 1.14.4
• NarratorBind 1.0.1+build.2
• NBT Tooltip mod 0.3
• optifine (not sure build number)
• Shulker Box tooltip 1.3.1+1.14.4
• Tooltip Autowrap 1.0.0
• Tweakeroo 0.9.10 and 0.10.0-dev.20190905.022216
• Voxelmap 1.9.13

Newer log. And I may have found the culprit. Looks like I might not have cleared out an earlier modpack fully when I set up this one. And a new instance of it works fine, but the current one is borked, just with Tweakeroo though.

crash-2019-11-02_15.40.55-client.txt

it is a conflict with a mixin between tweakeroo and a mod from deftware

Does this build fix the crash? https://masa.dy.fi/tmp/minecraft/mods/tweakeroo/tweakeroo-fabric-1.14.4-0.10.0-dev.20191103.001700.jar

Will test right away, as eating dinner.

EDIT - tested it and it did not help with that instance but figured out that it was leftover stuff from a mod I had been testing and had not removed everything for, which I thought I had.

Works fine when I cleaned out the folders and reinstalled the mods.