Graphical Glitch through Linedef(?)

[Azuris]

As you can see below in the Pictures, i have some Graphical Errors in my Map in some "Corners".

Five Appear in every Corner of a Star i've made on the Ground.
One in a Cave on a more random Place.

Can someone be so kindly and explain me how these occure and how i can avoid them / repair them?

If you need some more Pictures or Informations, ask :)

Thank you in Advance

 

(Working on Ultimate Doom Builder and testing with Choclate Doom)

Edit: Analysis Mode doesn't show me anything.

Edit2: When playing on DOSBOX those on the Star are harder to trigger, that one in the Cave does not appear (at least i can't find the right Spot to trigger it).

 

Edited February 21, 2021 by Azuris

[boris]

It's a common problem: https://doomwiki.org/wiki/Slime_trail

[Mr.Rocket]

Sometimes, moving a couple vertices around and putting them back can alleviate the problem. 

[Azuris]

Oke, thank you.

Seeing the Article i remember that i have seen it before in the Main Game...

Making your own Map something like this becomes more obvious/stuck in your head.