I have a dark mode on Firefox (or rather automatic, aligning on system dark theme), and I had Dark Vector also. Going back to Vector stops making the pages light grey, but then the background is black, which I find more tiring for the eyes than white.
There is a "Light mode » option at the top right, between Preferences and Watchlist, but it isn't a proper link (screen shot :
).
I prefer the dark grey colours of the Dark Vector apparrance, but I can't seem to have it without having all the other web pages in light theme.
What is strange is it was working fine a few days ago, and now I have either the wrong colours with Dark Vector (
), or the pitch black background without it (
).
The colours are fine on my preference page (
), but not elsewhere on this wiki.