Firefox

I wonder if they were using FF back when they had the Panorama feature back in the day. That many tabs seems like it would be great for organizing everything. It is almost hilarious to think that FF was so far ahead of the game that it just didn't make sense. Now all the other major browsers are adding some kind of tab groups feature.

The way FF did it was cool and was like having virtual desktops but groups of tabs. Aside from proper vertical tabs that keeps theme and doesn't require hacking settings to get rid of the horizontal row (Edge and Brave are good examples as their hover to expand titles and collapse when using the pages are smooth). Bringing back grouping tabs like Panorama had them would be really cool to have again.

Though I would love to see a blend of nice vertical tabs and groups like what I see in screenshots of browsers like Arc. Very different looking but in a good way. If FF could make their own spin of that UI work with both vertical and horizontal tabs. It would be dope af.