To improve the ease of use for PGP based mail encryption, it'd be great if KMail could join the ranks  of autocrypt  supporting mail client.s
Basically, Autocrypt just adds another mail header which includes meta informations for further encryption, including the public key of the sender.
*** Bug 388332 has been marked as a duplicate of this bug. ***
Autocrypt is more than just adding another mail header. In particular, autocrypt is about maintaining state of the peer's keys, and providing a simple interface for the user to be able to encrypt when they want to.
It would be great to have autocrypt support in kmail!
There is already a Phabricator task tagged for KDE Privacy Goal about this. Thus confirming.
Autocrypt support for kmail
This is a junior job suitable for new contributors. So if you like to help, get in touch with KDEPIM team.
Otherwise please have patience until someone else implements it.
KMail has now a basic Autocrypt support for more information see the blog post. Currently you need to enable it by modifiing the configfiles by hand. Maybe the upcoming version 21.04 will have this feature available for users via dialogs.
You still need to select by hand you want to encrypt, even when the recipient is found to be able to decrypt... But it's great to see it's getting there...
Git commit 6ac0bac57ae8bcba77e765700ddcaccb8229304e by Sandro Knauß.
Committed on 14/03/2021 at 19:10.
Pushed by knauss into branch 'master'.
KMComposerWin: Add Autocrypt support for recipients.
If Autocrypt key is detected for a recipient, the mail is automatically
encrypted and the user sees feedback, that an encryption key is
M +47 -1 src/editor/kmcomposerwin.cpp