Firefox users who want to use the computer keyboard to navigate their open tabs are left with the CTRL 1-9 shortcuts that allow them to switch to the first eight tabs that are open in the web browser. There is no other way of accessing tabs beyond that count by default.
Tab Navigator introduces an ingenious [...]
Firefox Tab Navigator
Firefox Numbered Tabs
A rather unknown feature of Firefox is the ability to quickly switch tabs with the shortcut [CTRL 1-9]. It obviously only works for the first nine tabs, additional tabs cannot be accessed with the shortcut. If less than nine tabs are open pressing a number that corresponds to a non existing tab will activate the [...]

