"Textmarker" makes text invisible in rich text editor

Low-hanging fruit:

How to reproduce

1. Add string in any given textarea in markdown mode: <mark>Test the textmarker style</mark>, save.
2. It should look like this now: Test the textmarker style.
3. Edit again and switch to rich text editor.
4. The string disappears visually

Bugfix

1. Find the (S)CSS file responsible for producing .md mark
2. Remove z-index: -1; (at least I see no reason for this)

I tried to find that file but gave up, sorry for this. I'm new to GitLab development.

bugux Category:Text Editors