Sometimes, when emails are manually migrated or restored from a manual backup, it is required to update mailboxes' indexes so migrated/restored emails are available via IMAP.
Such functionality could be added to the utility "plesk repair mail" so it is possible to update indexes in automated way.

Ability to use MySQL as an extension to Dovecot
Business case: using MySQL database for centralized authentication to email accounts.

Allow greylisting control individually per user, while maintaining the control on a subscription/level, not server-wide

We use the following configuration on Plesk for Windows: in MailEnable postoffices folder, domains' folders are junctions to folders inside subscriptions' web folder (e.g. C:\inetpub\vhosts\example.com\email). In Plesk Onyx with such setup, statistics were calculated successfully but in Obsidian, it stopped counting the size of junctions, so the mail statistics is counted as 0.
This setup is important for us, so please return the support for domains' mail folders as junctions.

Hello,
I have noticed that I use and also need more and more eMail addresses for different websites.
If only to see which website may have been hacked and turn off the SPAM on it. Currently it is possible to create aliases.

However, the list becomes very confusing, as soon as some addresses were deposited.

There is open source code from Anonaddy on Github.
It would be great if this would be integrated and also the addon for Chrome/Firefox is adapted so that this works together with the anonaddy in Plesk.

It is no longer possible to create mail accounts without a password in Plesk Obsidian. However it is required to create such mail addresses for Forwarding as example.

Implement outgoing email limits by IP

Add to Plesk Email Security setting that shows weekly difference in mail statistics. For example, show "+55 emails sent to spam last week"

When there is a SmarterMail service running on the same server with Plesk, it would be great to have an option to create an account in Plesk with the same domain and attach the SmarterMail content.

Add an ability to register webmail in the following format: http://mail.<domain>, so the customer can open it via http://mail.example.com

Very simple one this. I have email account with a huge list of aliases. I have to scroll a looooong way down to get the box to add a new one. Put the box where a new alias can be entered above the existing list, not at the base. Thanks.

Sometimes it is required to use another sender FROM without changing it automatically.

Can not mark ham messages as spam serverwide on Plesk Email Security Pro. Many spam messages and senders look HAM but actually spam. This should be handled by server admin, not individual email clients.

Add a setting to disable mail forwarding to certain domains in Panel for global configuration so that on user side wont be allowed to put the certain domains in the Forwarding Email in the Plesk Panel. Thank you.

like <request_subject> allows to repeat the subject in the auto-reply, it would be nice to have a similiar tag like "<request_body>" making it possible to include the sender's mail body in the auto-reply message body.
This would make the handling of web form request a lot easier on plesk.

Due to IT security implementations it is often necessary to know when users changed their password to force them to change it again.
From this change, new features could be added to improve the service.
-Number of saved passwords
-Force password change every x days
-Send password change reminder

Allow the user to define expressions or words in the subject or body of the message that would classify the email as SPAM. For example: if a rule was created that classifies as SPAM every email that has the word 'OFFER' in the subject.
Just blacklisting by email / domain is not enough, because SPAMERS change domains very easily.