zeyple VS Roundcube

Setup Postfix to use a mail relay: https://www.howtoforge.com/tutorial/configure-postfix-to-use-gmail-as-a-mail-relay/. That tutorial's for Gmail, but you can really use any SMTP provider you want. If you use GnuPG, you can even encrypt the notification emails with zeyple: https://github.com/infertux/zeyple.

transparent encryption of stored emails per default like in the Dovecot mail-crypt plugin plus the option for automatic encryption like in Zeyple

I have tried several, and liked none of them. I'm currently on Geary, but it's lacking in functionality, and it has things like search results being a bit different upon each of my searches. Starred messages cannot be shown on top. Eyeroll.

I think Evolution and Thunderbird are the top contenders, and of the self-hosted ones, Roundcube.

https://wiki.gnome.org/Apps/Geary

https://roundcube.net/

The GitHub issue talking about this [1] is such a mess too. Maintainers closing the question with a vague non-answer, deleting comments left and right, etc. Sounds like someone stole the money and everyone is either complicit or too embarrassed to admit that it happened.

[1] https://github.com/roundcube/roundcubemail/issues/6030

https://github.com/roundcube/roundcubemail/blob/master/SQL/mysql.initial.sql Take a look at the tables an you get a idea, session for the app, users-table, contacts-table, dictionary, etc.

You could try a standalone email client like Mozilla's Thunderbird, or if you're experienced running a web server, you could check out something like Roundcube. I suppose you could even run it locally if you're familiar with PHP and/or Docker.

Like... https://roundcube.net/

What I really miss is a "web companion" for Thunderbird, basically something like https://roundcube.net/ or https://www.horde.org/apps/webmail, but a bit more powerful and with better UX. I'd like to use a Google Addressbook within such app, for example (there is a completely outdated plug-in for RoundCube). Another important thing would be powerful and fast search.

Alternatively if you want to keep what you have I wouldn't recommend using the SoGO even though it's the nicest and most modern option. Mainly because it's a full groupware client and will require a lot of configuration. Instead using Roundcube is probably your best option

Roundcube might fit the bill for you.

I'd do it with a local IMAP server in conjunction with a webmail client that connects to it. Dovecot is a fantastic and easy to use IMAP server. Webmail clients are a pretty personal thing, but the last time I used Roundcube it seemed pretty good.