Sorry for combining three points in this bug, but I am seeking UI consistency here. One can experiment with this UI with 3 messages. First, click on each message so that they are in the state "read". Click on one message and select the menu item 'Message' -> 'Mark' -> 'As Read'. This marks the message as "unread". Admittedly, there is a check next to the menu item when it is "read", and that is not there when it is "unread", but this is unnecessarily subtle. Perhaps if the selected messages are "read", then the menu item can be changed so that it says 'Message' -> 'Mark' -> 'As Unread'. Dynamically changing the menu item names (in Mac OS X) has been possible for a long time. Second, if one selects a message which is read and, at the same time, a message which is unread, and one selects the 'Message' -> 'Mark' -> 'As Read' menu item, what is supposed to happen? I think that what happens now, that all the selected messages get marked as "unread" is the least intuitive result. I would argue that the result should be either that all the selected messages be marked as "read", or that if the selection contains both read and unread messages, the menu item is disabled, since it has no clear action to take. Third, the 'Message' -> 'Mark' -> 'Thread As Read' should not act differently than the 'As Read' menu item. It should act on different messages (as it does), but the action should be the same. Right now, the 'Message' -> 'Mark' -> 'Thread As Read' acts on any messages selected and all messages in the threads of any of the messages. Its action is to unconditionally mark the messages as read. As the 'As Read' menu item should do also. I can map out the results of the menu items on different messages in different states as a state machine if that will make more sense and if it is requested.

Yeah, this is bizarre. Here's how I did it: I had a bunch of messages I wanted to mark as unread. So I select all of them, right click, and find "Mark as read". I click on that and voila! They are all marked as UNread. Further, there's another menu item: Mark as all read. HUH? Well, "Mark as all read" means "Mark as read", and "Mark as read" means "Mark as unread". Perhaps it's a 'red', 'reed' problem, but it really isn't clear.

partial dupe of bug 327828? (I didn't read it all, so I don't know)

belongs in front end. please read comment 2 and post your conclusion :)

It seems a dupe of bug #327828. Feel free to reopen it if I'm wrong.