What is wrong with this wall?

[HotCoffee]

The wall is a linedef marked as "impassable" "block monster" and "double sided", it has a only a middle texture (brown wall) and it's in the middle of a sector. I made this to hide a monster behind it that when it sees the player it will move and get teleported, on crispy doom and gzdoom the wall looks normal but on chocolate-doom I get this:

[Aurelius]

It's called the medusa effect, and is caused by your middle texture being made out of more than one patch. You can make a single patch version of the texture in question and it should work fine.