6 files declare their use of GroupContentEnablerBase in Group 8

EntityTestAsContent.php in tests/modules/group_test_plugin/src/Plugin/GroupContentEnabler/EntityTestAsContent.php

GroupAsContent.php in tests/modules/group_test_plugin/src/Plugin/GroupContentEnabler/GroupAsContent.php

GroupMembership.php in src/Plugin/GroupContentEnabler/GroupMembership.php

GroupNode.php in modules/gnode/src/Plugin/GroupContentEnabler/GroupNode.php

NodeAsContent.php in tests/modules/group_test_plugin/src/Plugin/GroupContentEnabler/NodeAsContent.php

UserAsContent.php in tests/modules/group_test_plugin/src/Plugin/GroupContentEnabler/UserAsContent.php