Dark reader is great. It can also be used to prevent fingerprinting based on your preference, as most are configured to light mode by default.
However it often makes the site nearly or completely unusable, as it isn't (and can't) always be 100% correct. Having dark mode configured by the site is often much more useful.
or... just lower your monitor brightness so you don't feel like you need dark mode, which is actually worse in every way than just using the correct monitor brightness.
Sorry I didn't mean any negatively towards you there. I just remember what the site was like before it hit my blocklist. It was before chatgpt got big but everything I read on there was scraped info from other sites and full of errors
Firefox with the extension "Dark Reader" is great. There are some websites I have to disable it, but it's rare. I also recommend uBlock Origin.
Edit: I see someone already recommended dark reader. But it really is a must have extension. It knows if your system theme is set to light or dark and matches it automatically.
making it a per-profile settings does not exclude making it available per-device or per-visit. it's not especially difficult to store a flag in localStorage or a cookie. hell, you can even use CSS to detect OS dark mode preference settings and have it change automatically with no user input at all.
Dark mode is incorporated into most modern browsers and OSs at this point. If your system is set to dark mode, your browser will run in dark mode also notify the site that you request dark mode. No server settings or accounts required. The site just needs to be configured to respect that request.
Aside from that they can also store your preference according to cookies.
I just want them to follow system default for guest user(s).
they probably require an account because they have a system set up in a way where it's mostly a server-side app and ui settings are only stored on the server
This makes more sense for signed in user(s).
No dark mode unless you register, is what I consider to be a asshole design choice.