since about the beginning of November, I have troubles in using mail clients to access Office 365 mailboxes via IMAP. Specifically, it has become impossible to subscribe to IMAP folders, so that the MUA will only show "INBOX" and "TRASH"
As a workaround it is possible to configure the MUA to display all the folders it finds, regardless of any subscription, but this is clearly undesirable.
Does anyone know if in November there was the rollout of some new server code or feature on Microsoft side? Is this likely to be a bug with MS implementation of IMAP (so basically, one can just hope it will be fixed)?
Alternatively, is it likely to be an issue of the MUA? I know the issue is visible in thunderbird (as I see it there) and also in Gnome Evolution (from reports at https://answers.microsoft.com/en-us/msoffice/forum/all/unable-to-subscribe-to-office-365-imap-folders/c9273f2c-b63c-4647-87ce-bab6625814e6).
Alternatively, can it be a configuration problem of the business buying the service from MS?
Finally, is there any workaround that can be implemented in the MUA, apart from ignoring subscriptions and showing everything? Can the filtering of the folders to be shown be configured in the client regardless of subscriptions on the server (guess this might be client dependent, looking for solutions for thunderbird if possible).
