Nice tip, although remembering using it and meanwhile it made the forums "dark mode", it changes texts etc and at the time it wasn't pretty. Hence stop using that plugin.
Its on the scratch list - thing to keep in mind is this was basically a beta - the site was massively late through no fault of our own and I just wanted to get it live and then work on changes as we went along.
I hear you about dark mode though and it will be implemented (Ive moved it up the todo list)
If you use chrome there's a button at the top right next to extensions that toggles on dark mode for all sites. Well works on the forums not the new site