Is there a single mail client that has a nice UI, can support both
html mail
and maildir format, as well as syncing caldav calendars and support gog
encryption? Of course supporting multiple email accounts including imap is
essential.
claws does all that except the caldav. Its a mail program not a calendar
and there are better calendar apps. I have a bit over a million items of
email in it right now and its not yet exploded although it might with
them all in one folder ;)
Email clients have been a slight irritation for me since I never
found one
that supports everything that I need in a single application.