Yeah, basically. The flags with [] characters are added to gmail (in my
case) by OtherInbox's Organizer app. I contacted them but haven't heard
back yet.

On Wed, Jul 16, 2014 at 4:07 PM, R. David Murray <report@bugs.python.org>
wrote:

>
> R. David Murray added the comment:
>
> Just to make sure I understand: the issue is that gmail may produce flags
> with [] in them, and imaplib currently fails to process such flags when it
> receives them from gmail?
>
> In principle I think we would not want to allow imaplib to be used to
> create such flags unless the user specifies some sort of "I want to violate
> the RFC" flag (which they might want to do, for example, to run tests
> against gmail :)  But currently it looks like it can?  (I haven't looked at
> this in enough detail to be sure.)  If that's true we probably have to
> continue to allow it for backward compatibility reasons, but we should
> document the RFC violation and possible consequences (an IMAP server
> rejecting such flags).
>
> ----------
>
> _______________________________________
> Python tracker <report@bugs.python.org>
> <http://bugs.python.org/issue21815>
> _______________________________________
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