Ongoing Issue: Mail and Gmail "message read" synchronization problems
<p>Gmail users have found that when using Apple Mail or Mozilla Thunderbird to view e-mails, messages that are marked as read by another source (the Web viewer or another email client) are not being flagged as such by the server.</p>
Gmail users have found that when using Apple Mail or Mozilla Thunderbird to view e-mails, messages that are marked as read by another source (the Web viewer or another email client) are not being flagged as such by the server.
If you delete emails or otherwise manage them in files and folders (Gmail labels) the changes will be properly reflected in Mail or Thunderbird; however, the "read" flag does not seem to carry over between email clients.
While Google implements IMAP support in its Gmail service, it uses very nonstandard approaches to the IMAP protocol in order to support its plethora of Gmail-specific features, and for some reason this has broken the way IMAP handles the "message read" status.
This problem has affected almost all Gmail users who have their accounts setup via IMAP in an email client, and is clearly a fault in how the Gmail service handles the IMAP protocol. Let's hope Google fixes this soon, but for now there are no known workarounds.
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