[smcleod]

This is legitimately the only thing I've been asking for from Firefox the last <many> years, I don't really care about webgpu, usb device access would be nice as would fine grained user-controllable permissions for extensions - but all I really want every single day is a better way to group tabs. Hell - just being able to group them by colour like you can in Chrome would be a huge leap forward. I've tried all the well known extensions and I'm not a fan of any of them.

[Terretta]

If you use Mac and haven't looked outside Firefox, note that vertical tabs are in Safari, with groups, and group sync.

Vertical tabs (plus tree tabs) are also in Kagi Orion. Which unlike Safari also runs (a subset of) Firefox (and Chrome) extensions, about 70% as of their last FAQ update:

https://browser.kagi.com/faq.html#extensions