Iceberg's custom VertexConsumer conflicts with sodium, which results in a crash.
sourced from jellysquid themself
Mod version 1.4.3 on 1.19.4

Crash report

Only current known fixes are:

• disable the 3D model in the tooltip via the config
• downgrade to sodium 4.8 or lower
• downgrade iceberg to 1.1.8 (compatible with sodium 4.10)

The version of Iceberg you are using has been archived due to this issue (it was made to be exclusively compatible with Sodium 0.4.11 which has been taken down). Please try version 1.1.9.1 (just released) with Sodium version 0.4.10. Feel free to reopen this issue if this does not solve the problem.