Thanks, I just tried them both. They don't work well, sorry. Aside from the terrible UI, if I open a bunch of tabs and give them a name, then close the window, and open a new window, the groups are gone. This makes no sense. The groups must be persistent. Once named, they must never disappear.
If I open a bunch of tabs as a named group, then open a new, blank window, then enter the extension's UI, the list of groups only has my current window. Makes absolutely no sense. The "group" state has to be global (and visible on all devices, which I doubt this does).
The extensions also seem to be doing something weird by hiding tabs, which Firefox was warning me about.
I understand. I don't mind, because I keep single window and use those groups like windows. But I've been lucky with not stumbling upon weak persistency, so I get how it could be frustrating.
Warning about tab hiding is normal. I assume that something that you would find perfect also would have to use tab hiding.
They need more work or something separate, because the manual resizing of groups seems like a busy-work. I would like something more like Simplified Tab Groups, but with good syncing as you said. I'm not sure how would it work with current Firefox APIs though. If extension shows you the same group for two separate widows, what would happen if you would select the group in both of them? It would have to create additional tabs so they would not be shared. Also I'm not sure if tab hiding API allows to mix tabs from different windows. I think that what you want is not possible currently as an extension.
Not sure why tab hiding is needed. I want the extension to track my activity, not interfere.
The only two point when it needs to do something is when I want to restore a "group" that has been saved. If I close tabs or windows, nothing needs to be done; my hypothetical extension would already have saved their state to a database of some kind on every change.
As for multiple windows: An "open" group would be associated with a single window. You wouldn't be able to open a new window for a group that's already live and in use.
If I open a bunch of tabs as a named group, then open a new, blank window, then enter the extension's UI, the list of groups only has my current window. Makes absolutely no sense. The "group" state has to be global (and visible on all devices, which I doubt this does).
The extensions also seem to be doing something weird by hiding tabs, which Firefox was warning me about.