Samsung Internet Browser: <a href="https://en.wikipedia.org/wiki/Samsung_Internet_Browser" rel="nofollow">https://en.wikipedia.org/wiki/Samsung_Internet_Browser</a><p>Chromium-based browser for Android.
Firefox also has a kind of forced dark mode, even inverting images, which is on by default regardless of system settings and impossible to disable. (Maybe only on iOS and maybe only on an older version.)