it'd be very practical to have Tab Menu Tree Style/Nested since in a glance one can see which tab comes from where and when the parent tabs and children tabs are obvious you can decide faster which tab you're going to switch/close/Etc. btw the Tab Menu is already nested by categories Open Tabs and Recently Closed Tabs. why not extend it a bit further and assign a handy keyboard/mouse shortcut to it and make it a very useful feature, and at the same time eliminate the need for some half-assed tab-sorting extensions to organize the tabs.