handle mails snoozed via gmail

[aspiers]

Gmail UI has a snooze feature:

By default it seems that lieer does not sync any snoozed label, even though you can query is:snoozed (or label:snoozed) in gmail as mentioned in #32 (comment).

This is presumably because the Gmail API doesn't expose snooze features, as covered by Issue #109952618 in Google's issue tracker. That issue has an incredible 4543 votes at the time of writing, yet has been totally ignored by Google ever since it was reported in 2018. That speaks volumes about the level of maintenance the Gmail API is enjoying.

Maybe one way to handle this would be to do a label:snoozed query at the end of each partial or full sync, retroactively ensuring that only mails returned by that query have the snoozed label in notmuch. However without full API support this would have to remain a one-way sync of that special label, because there would probably be no way to propagate changes to that label back to Gmail - unless users.messages.modify actually happens to support this without documenting it.