**Active** Stylesheet editor bug

Here You go.

Ive had this or something similar for years.
I am not sure if it is my custom workspace that is causing it.
ive documented it lightly on the youtube vid

I will try it later on standard 3 col workspace or maybe tomorow,
I dont think i can look at the screen and discern differences anymore tbh, it has scrambled me for the past hour or two.

Is this me, with mistaken understanding of how this is working, due to a root class, and other things/pseudo classes applied to that one?

I can no longer tell, it frazzled me.
if its me,
point me at the correct tutorial as I’ve obviously forgotten and can no longer see the woods for trees!