after killing mob and dropping adder's fork and getting poisoned, the surrounding constructions were deformed

Version of Minecraft, Bewitchment, Forge, Patchouli, LLibrary and Baubles used

forge 14.23.5.2808
Bewitchment-1.12.2-0.0.19.32-indev.jar
Patchouli-1.0-17.jar
llibrary-1.7.17-1.12.2.jar
Baubles-1.12-1.5.2.jar

That's definitely some other mod messing with rendering. Those are gl vertexes messing up.
What's in your pack? If you have optifine, albedo, or any other mod that messes with rendering, try and remove that first, and see if it still happens

i have only Bewitchmen,Patchouli,llibrary,Baubles and jei

Might be llibrary then, that's the only coremod

LLibrary is required for the mod to run

I know, but it still can be the cause

That's definitely some other mod messing with rendering. Those are gl vertexes messing up.
What's in your pack? If you have optifine, albedo, or any other mod that messes with rendering, try and remove that first, and see if it still happens

What rendering in question is being messed with?

I'm legitimately unsure.

LLibrary could very well be causing it, but I don't believe it'd be rendering anything on its own. It'd have to be interfering with something else's rendering.

Perhaps try updating your graphics drivers? I noticed you're on a Linux distro, possible they're out of date.