I'm getting this error in the log:

[18:03:22] [main/ERROR]: Write access detected to @Final field field_1705:Lnet/minecraft/class_329; in inventoryhotswap.mixins.json:HideHudMixin::handler$zmj000$onHudRender

This should be fixed in the latest 1.17 fabric release 1.2.0 as I went with a different method for modifying the HUD. Will add changes to 1.16 when I get a chance.

Me too, it doesn't seem harmful, but I don't know if you can patch it or not.