Checkerboard box showing up on screen

[Hardcawcanary]

Same issue as this post

Floating Texture when changing health.

Hey all, I’ve just added a health selector to my creative map. However, when shooting the trigger to change health, a floating texture runs vertically up my screen (video attached). I was wondering if anyone had experienced this and would know how to fix it! The devices used were a class selector, class designer, trigger and mutator zone. Any help is appreciated