If it's possible, I think the sync page in the tab tray that shows the tabs you have on other devices should also show the tab groups from those devices. I have a lot of grouped tabs on my computer, and I've noticed that when I'm using the mobile app...
It would work so well if Firefox didn't only just have tab groups on mobile, but if you were also able to sync them with your desktop tab groups and vice versa. Like how for instance you're always able to access your tab groups on desktop by clicking...