Both the Drafts and Outbox folders are different from all other folders in that they show messages that have not yet been sent. In the case of Drafts, people open the folder because they either want to resume editing a specific message or trash drafts that are no longer needed. In the case of the Outbox, people open it to view messages that have not been sent, not been saved, or to trash a specific message before it is sent.

Although these operations all relate to individual messages, Geary currently treats these folders the same as others, in that it shows the complete conversation around the message rather than the individual messages when selected. This is useful for the same reason as conversations are generally useful, but it is also confusing, especially when it comes to deleting messages from the folder: If you delete a conversation containing a draft in the Drafts folder, does it delete the whole conversation? Probably not, but how can you be sure?

Further, in Bug 789078 we probably want to move to a model where say Trashing a conversation trashes the *entire* conversation, including out of folder-message). If that becomes the case, the current Drafts and Outbox behaviour will become more problematic.

One solution to this is to simply show individual messages in the Drafts and Outbox folders in the conversation list, and when selected rather than loading the complete conversation simply load the individual message. This makes it clear that operations on the messages will apply only to the message itself.

Since it can still be useful to see the conversation around it, we should add a GtkInfoBar in all cases for messages in these folders that has a "Open Conversation" button. Clicking that will switch folder and load the complete conversation. For drafts:

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  *Draft Message*                       
  This message has not yet been sent.   [Open Conversation] [Resume Editing]
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And for messages in the outbox:

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  *Queued Message*                       
  This message has not yet been sent.   [Open Conversation] [Cancel Sending]
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