[m_t]

This looks like a good replacement of the old tab group Firefox used to have. The fact we can assign them a container is really promising, I'll give it a go!

[cmehdy]

I found this[0] minimal style (not by me) particularly useful, with auto-folding and a thin visual footprint.

[0] https://github.com/ongots/firefox-sidebery-minimal-style (screenshots further down the page)

[Vinnl]

For me it replaced both my tab groups extension and vertical tabs extension. It's a godsend, although a little bit buggy every now and then.