This extension is the reason I use Firefox as my main browser rather than Chrome or Edge. It is got so many options and settings to customize to your needs that it is invaluable to the tab hoarder.

Useful to use in combination with Auto Tab Discard Extension to prevent many tabs slowing down your machine.

Very thoughtful add that makes my job much easier

Great extension for vertical tabs. Works flawlessly, no bugs and no crappy animations like other extensions I tested. Grouping tabs by right-clicking is super useful, it's like bookmarks but better. Speaking of bookmarks, you can select tabs and bookmark all of them at once, super useful. The sections, used with Firefox Containers, are super great to separate work, school, and personal things. Unloading tabs is also a functionality that I think is super useful when you want to keep tabs in the sidebar but don't have them loaded.

olay

So much more responsive and performant than Tree Style Tab (aka TST) if you have way too many tabs open. This is the one you want.

Perfect

I really don't know how I lived without it before.

Excellent extension. So much more than just vertical tabs. Panels can be configured to match containers.

Would highly recommend.