Firefox toolbar button to switch to the previous active tab
https://addons.mozilla.org/firefox/addon/switch-to-previous-active-tab/
Firefox toolbar button to switch to the last accessed tab (and MRU popup)
Firefox toolbar button to switch to the previous active tab
https://addons.mozilla.org/firefox/addon/switch-to-previous-active-tab/
Firefox toolbar button to switch to the last accessed tab (and MRU popup)
Mozilla Public License 2.0