Not a flying screen-bug, no, this is a very known and sad fact of equipped armour textures glitching, in this case, the heroes expansion mod (including addons), which is i believe a part of lucraft : core mod.

Here I give ya a very classy screenshot of this issue

I hope i would see this mod's, armours compatible one day, would be amazing since mo'bends is a must-have mod.

Cheers!

Looking at how Lucraft: Core implements their armors, it won't be compatible with Mo' Bends unless they adhere to the guidelines I put forward: https://github.com/mobends/MoBends/wiki/Armor-Mutation

Source-code for the armor model for future reference: https://gitlab.com/threetag/legacy/LucraftCore/-/blob/master/src/main/java/lucraft/mods/lucraftcore/superpowers/models/ModelBipedSuitSet.java

The upcoming Mo' Bends 1.0.0 should work with most mod armors out of the box, I'll come back to this issue once it releases. Thanks for reporting it 😄