I tested Firefox 115.4ESR with Pinephone Keyboard.

Works fine, not have Maemo UI, but you can get full-screen with F11 key, to get it F11 work you need fix keyboard layout:
https://talk.maemo.org/showpost.php?...1&postcount=46

I did not make any tricks what found in Leste wiki. By default you can scrolling with keys. With touch screen you only select link (or select text for copy) with touch screen. And actually that is very handy for copy-paste (with ctrl-C and ctrl-v) that way.

Firefox 115 might work also with Droid4. It is too much for N900, still hoping that somebody try make old Maemo Firefox Fennec version to Leste.