Kostya,
Originally I thought this was a limitation of IMAP but having seen a recent reply you made to another post I'm not so sure.
Simply put, I have 2 devices, but the message read state is not being persisted across both devices, even after a sync on both. So, emails are read on one device, synced up but even after a sync on the second device they're still showing as unread on that 2nd device.
Thanks!
R
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