Flatpak: Share NSS database with the system
I've installed the precompiled Evolution 3.38.3 from Flathub.
I've imported my settings from a backup of the original Evolution 3.30 on Debian 10.
The only point is I'm not able to import my private certificate for encrypting, because Evolution asks for the password of the NSS database, and it apparently uses a different NSS database than the default one in my home folder in the sandbox.
Edited by Milan Crha