The firefox version for android tablets has a very inaccessible user intreface. The interface should be very similar or identical to the desktop one.
The full view of open browser tabs on the toolbar is missing. The interface looks like simply scaled down from the smartphone one: we have an address bar and next to it on the right an icon with a rectangle inside which a number indicating the number of open tabs. This is very inconvenient to use.
Tablets usually have screens of 10-11 inches, tablets over 12 inches are becoming more and more popular. So there is enough space to place the tabs normally, as in the desktop version. All competitors like Chrome, Opera, Brave and others have long since introduced such solutions.