The action "Mark Thread as Read" should be disabled if the thread is already marked read. And of course the other way around: The action "Mark Thread as Unread" should be disabled if the thread is already marked unread Whereas: Offer both actions if some messages in the thread are marked read, while others aren't. This would: - improve consistency with "Mark Message as Un/Read" - add some visual feedback about the thread's status - helps simplifying the UI by reducing the list of available options to chose from Reproducible: Always