Gmail bounce message inactive inbox processed as Soft Bounce

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Affected version

2.3.7

This common Gmail bounce message is processed as a Soft Bounce:

Action: failed
Final-Recipient: rfc822; xxx@gmail.com
Diagnostic-Code: smtp; 552-5.2.2 The recipient's inbox is out of storage space and inactive. Please
 552-5.2.2 direct the recipient to
 552 5.2.2  https://support.google.com/mail/?p=OverQuotaPerm 5b1f17b1804b1-4775d265d99si1629965e9.16 - gsmtp
Status: 5.2.2

While this is technically classified correctly as 552 (inbox_full), this is practically incorrect. This inbox is also inactive and should therefore be processed as a hard bounce. As gmail is the main email provider these days and therefore high impact, its a bounce message that should be taken into consideration.

It would be best to look for:
Diagnostic-Code: smtp; 552-5.2.2 The recipient's inbox is out of storage space and inactive.
And classify such bounce messages as hard bounce.