I've been using Tree Style Tab [1] in Firefox for a while now. IMO it's much better than standard tabs. https://addons.mozilla.org/en-GB/firefox/addon/tree-sty

I've been using Tree Style Tab [1] in Firefox for a while now. IMO it's much better than standard tabs. https://addons.mozilla.org/en-GB/firefox/addon/tree-style-tab/ https://addons.mozilla.org/en-GB/firefox/addon/tree-style-ta... (To anyone who plans to try it, you may need to edit userChrome.css to turn off the top tabs; there's guides on this. I also recommend tweaking TST's settings, imposing a limit on nesting, and preventing auto switching tabs )