The addon is nearly perfect and I love the group icons. It`s the best addon I´ve seen to manage tabs. But sadly it`s not working correctly anymore. When I change the group, some of the tabs change the group with me and stay active. Are you aware of this bug (probably from a Firefox update, since before it was running great)? I use Firefox Quantum.

Update: It seems like other Tab Group Addons are having the same problems.