We have replicated this bug with a 1.16 texture pack, any modification to the GUI.png and GUI2.png file under textures/gui/ leads to the whole GUI file showing instead of the specific reference point. So far I haven't found any pack that has a modified GUI.png that isn't affected by this bug.
Callum Pearl
We have replicated this bug with a 1.16 texture pack, any modification to the GUI.png and GUI2.png file under textures/gui/ leads to the whole GUI file showing instead of the specific reference point. So far I haven't found any pack that has a modified GUI.png that isn't affected by this bug.