Then I guess you haven't tried a recent version of: https://addons.mozilla.org/en-US/firefox/addon/tree-style-tab/ https://addons.mozilla.org/en-US/firefox/addo

Then I guess you haven't tried a recent version of: https://addons.mozilla.org/en-US/firefox/addon/tree-style-tab/ https://addons.mozilla.org/en-US/firefox/addon/tree-style-ta... I've been using it for, I think, 2-3 years. And it's come a long way since the early days when it was buggy. I suggest you give it another go with a more recent version. And don't be put off by the ugly screenshots on the add on page as it's not quite what it looks like anymore.