If you want to have the Dark Theme on Firefox for Android you have to... Tap the thre dots at the top left corner Tap Add-ons Then "For Firefox sugested Add-ons" (may sound a little different because I'm using the German version) Then you are at the Firefox Add-on page where you can download Add-ons which are like little programs taht are running inside your browser, like ad-blockers, themes, extra stuff, ... There you can search for "Dark Theme" or "Unicorn-Theme" or whatever you want. And just add it to your Firefox. But in different to the Firefox for Linux or Windows this will only cange a part of firefox, but better than nothing Greetings from Germany

nope.

Hi John

I recommend that you try the new Firefox Preview browser, available from the Google Play store. This has a great dark mode built in which will also dark theme some web pages.