Hi,
As you can see in Kasun's recent pull request[1], there's a proposed change to the table structure for pma__usergroups. Since pma__usergroups isn't yet part of a release, this won't affect anyone who has installed an official release. However, anyone (particularly us developers) who has created that table in the past month and a half will need to update their configuration.
I don't think we need to provide any further update or notice to the community, since most people running master would be subscribed to this list anyway.
Regards ~isaac