1.17.0-1324: new emails in IMAP inbox don't show if "Enable Optimizations" is on

[Christopher]

Using 1.17.0-1324 on a Samsing S9, Android 8. WiFi and 4G.

Using IMAP accounts, I've noticed recently that new emails no longer display in IMAP folders when manually refreshed. Occasionally I'd be able to 'kick' Aquamail into displaying them by toggling sync settings for folders; sometimes they would randomly start appearing after a dozen or more refreshes.

These accounts are hosted on Dreamhost, but I'm not sure if that's a factor in this problem. (Dreamhost recently updated their email hosting and have migrated customers to a new cluster, probably with newer MTAs).

I found that after disabling "Enable Optimizations" in Options & Folders -> IMAP Options (tap-and-hold on the account name to see the menu) emails now seem to be reliably appearing when I do a manual refresh.

I'll submit debug log via ticket, but thought it would be useful to make others aware of this. It puzzled me for a week as to why I was apparently getting no email to an account -- until I checked webmail

[Kostya Vasilyev]

It just means that the server claims CONDSTORE / QRESYNC but doesn't implement them properly.

For such "bad" servers - turning off "IMAP optimizations" is exactly the right thing to do.

[Christopher]

Thanks Kostya, I've filed a support ticket at Dreamhost to ask if they're aware of this. Thanks for continued development of your excellent mail app.