Comment 17 for bug 192092

(In reply to Marius Gedminas from comment #5)
> One thing I hadn't noticed before: moveTabForward/Backward leaves keyboard
> focus on the tab itself, which is something I didn't expect. This explains
> why I had occasional difficulties scrolling web pages with Space or
> PgUp/PgDown lately -- keyboard focus was in the wrong place, and I didn't
> notice. Any ideas how to avoid that focus change?

You can remove the focus change from the moveTabBackward, moveTabForward, moveTabToStart and moveTabToEnd methods and do it directly in the keypress handler where needed.