I've noticed that dark reader on occasion phones home to darkreader.org, also with a increasing amount of sponsored links on their page. So what does everyone think, are they safe right now or should they not be trusted?
https://github.com/darkreader/darkreader offer to review the source code.
Normally it isn't a problem if an app phones home to its homepage, eg, looking for updates. I think that DarkReader is trustworth. But it's anyway good to use the less extensions possible, because they always add a privacy flaw to the browser as any third party app. In Vivaldi instead of the Dark Reader i use the own Dark Mode in flags, it has also an ivert filter, among others, in the Page Actions menu.
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Just ran a Wireshark on it for 12 hours. The only thing it ever does is a frequent ping to their home site, but includes no useful data other than an IP address if you're not on VPN. I wouldn't worry about it personally. If it's a big deal, DNS block darkreader.org or block pings to it through your firewall... Chances are it's just to download the latest css rules when they have them or something.
Since I am not in anyway inclined to go read their code, I probably will just trust FF's "recommended" flag until there is an obvious problem. Of course, when it is like that, then it's too late. I tried the "Dark theme" on FF for a little bit, switch back to using Dark Reader in no time.
Op here, from what I have been seeing from everyone there are suspicious elements to darkreader, I'll keep it for right now though I may eventually switch to something else or use TamperMonkey or Stylus. Thanks everyone for all your knowledge and help.