Just created the phpmyadmin DB. The nav tree has a pma group (and a New node and nothing else) that contains all tables. I don't think having a group makes sense in this case.
Implemented with https://github.com/phpmyadmin/phpmyadmin/commit/24f1cb2265189210bffbc8b761718760f4703f5f
Implemented with https://github.com/phpmyadmin/phpmyadmin/commit/24f1cb2265189210bffbc8b761718760f4703f5f