When my head (username: Confabulate if it's needed) is rendered in an inventory GUI when I have custom model rendering on, it immediately crashes the game. The crash log is provided below:

crash-2023-12-29_15.53.59-client.txt

• OS: Arch Linux x86_64
• GPU: Intel UHD Graphics 630
• Mod loader: Fabric
• Mod list: ask for the list
• Game version: 1.20.2
• Mod version: 0.6.13a

Had the same problem with Sodium.
Downgrading the Sodium version fixes the problem.

Custom head work without crashes only in Sodium version 0.5.3 and lower.

• Tested it on 1.20.2 Fabric (fabirc v.0.15.0) (only work on this version)
• Tested with cpm and sodium mod only.
• The game crashes when rendered Custom head is displayed in the gui or on the armor stand.
  ( If the custom head isn't visible or the model doesn't load, the game won't crash. )

can replicate the crash as well--same exact stacktrace. downgrading to 0.5.3 sodium does indeed workaround the problem for me

I believe it was specifically this commit in sodium that broke it, given how it's the one where children gets changed to an unmodifiableMap in ModelPartMixin.java. the children should be updated before it gets copied by sodium to prevent the crash