tuxmain some if not most permissions are dependent on others π if only Admins can view discussions in your restricted tag, then they are the only ones that can like posts in them (if you have the Likes extension enabled). If you add other groups to be able to view discussion in your restricted tag, then that group will be selectable from the "Like Posts" permission drop-down and the same for "Rename discussions". Basically, a group won't be able to rename a discussion if they can't view any in your restricted tag.