So, i use a personal texture i made with two different ghast models that don't share the same .jem file, for some reasons, when the two models render at the same time, one of them, always the same one, gets his head resized. This works fine with optifine. To make it easier to find i've removed everything but the ghast model/textures from the pack.

This is my pack
!Casual Pack - Private- credits to Shrimpsby.zip

Expected behavior with optifine, only one ghast

Now with two Ghasts

Doing the same thing with EMF

Then with two ghasts again

-This is in 1.20.1
-EMF version is 1.0/1.0.1/1.0.2

This should be fixed in recent versions

This should be fixed in recent versions

Ok, I'll give it a look