So far it's... different? The tab handling is better, and I think I like having actual tabs in a mobile browser. I'm disappointed that the tab groups don't work as well as in Chrome. I like the link preview feature, in fact I could imagine all links opening like that by default (but that's not an option).
I don't find it all that customizable, that only seems to be true for the desktop version. For example, I can't get seem to rid of the history button (which is styled like a sidebar button despite opening full screen).
There is no reader mode. There are page actions, which let you apply all kinds of nonsensical CSS effects such as blur. But no reader mode. The built-in content blocker doesn't remove cosmetic annoyances as effectively as Ublock does, which makes me miss reader mode all the more.
There don't seem to be any add-ons.
Overall, not entirely convincing.
1. https://github.com/mozilla-mobile/fenix/issues/20012#issueco...