TL;DR (From Android Authority)
• Mozilla responded to a review mentioning the lack of tablet UI optimization for Firefox on Android.
• Mozilla confirmed that its team is not working on optimizing the tablet experience at the moment.
• Mozilla did, however, say that it hopes to revisit tablet optimization when time and resources permit.
I don’t expect much of anything from Firefox mobile except slowness and bugs tbh. I still use it because of the add-on support but there’s tab bugs that have existed for three years