Minecraft version

1.20

(Neo)Forge version

47.3.0

FramedBlocks version

9.3.1

Describe the bug

Upon loading up the save file with an existing frame block placed in the world, no matter what block or what texture is loaded into it, the chunk that the block sits on does not generate and the save no longer generates or functions. Removing the FramedBlocks mod makes the save work again.

How to reproduce the bug

Placing any kind of frame block in the world. Save & Exit, then reloading.

Expected behavior

Chunk does not load.

Additional details

Even taking out shaders and Distant Horizons does not fix the issue.

Crash log

https://gist.github.com/Dingbat1991/f22141ee0534ba0f38716ae49576fe86

Looks like upon further testing, Antique Atlas 4 (2.11.0) is causing some type of conflict. I'm going to take out this mod for now.

This issue is caused by Antique Atlas doing something that would be perfectly safe to do on Fabric but is not safe to do on Forge: when a chunk loads, Antique Atlas collects the "map colors" of the blocks. On Fabric this can only ever return a constant value and is therefore safe. Forge however allows mods to return a value that is dependent on dynamic data (which, in the case of FramedBlocks, is the camo applied to the given block). Due to the specific time where Antique Atlas requests this data, accessing the camo data causes the chunk loading process to lock up.
You'll have to report this to Antique Atlas and ask them whether they're willing to accomodate for issues caused by their mods being run on Forge. In case they ask, here is a thread dump of the deadlock: https://gist.github.com/XFactHD/ed9e6540cdec7cca846777b33a261827.