RFC 5465, "The IMAP NOTIFY Extension", February 2009Source of RFC: lemonade (app)
Errata ID: 4833
Reported By: Chris Newman
Date Reported: 2016-10-17
Section 5.2, 7 says:
Section 5.2 paragraph 4: ... The FETCH response(s) MUST follow any ESEARCH ADDTO responses. Section 7 paragraph 2: Note that the EXISTS response MUST precede any FETCH responses, and together they MUST precede the ESEARCH response.
As the RFC is internally inconsistent on this point, servers can have either behavior. I know of at least one deployed implementation that follows the MUST in section 7 rather than the one in section 5.2.
At this point I can't suggest specific corrected text, so this is a hold-for-document-update issue.