Evolution fails to connect to CalDAV via TLS outside Gnome's environment

[Simon Streit <simon@netpanic.org>]

Hello!

I've got a Radicale service running on a Guix host that has Let's
Encrypt certificates issued.  There are no problems connecting to it with
Icedove, or DAVx5.

Unfortunately Evolution, or its accompanying evolution-data-server fails
to sync the Calendars whenever it is launched outside of Gnome's desktop
environment.  The error it throws are:

--8<---------------cut here---------------start------------->8---
Failed to connect calendar “CalDAV : calendar”

TLS support is not available
--8<---------------cut here---------------end--------------->8---

Gnome-calendar obviously throws a very similar error:

--8<---------------cut here---------------start------------->8---
(gnome-calendar:19192): GcalManager-WARNING **: 13:53:39.487: source_credentials_required_cb: Failed to authenticate 'calendar': TLS support is not available
--8<---------------cut here---------------end--------------->8---

This is the same for calling Evolution inside Xfce, or i3. There is no
problem while being inside Gnome.  Though there is generally no problem
with using Mail in Evolution -- in case someone wonders. 

Does anyone else maybe use Evolution outside of Gnome?  And if so, do
you use CalDAV calendars?

I've compared my shell environments and manually copied exports that
where set in Gnome's environment.  Though that didn't help.
Gnome-keyring is running, and accessible.  I've also set up

--8<---------------cut here---------------start------------->8---
(service gnome-keyring-service-type)
--8<---------------cut here---------------start------------->8---

Even while inside Evolution it is possible to subscribe to CalDAV
calendars and have possible subscriptions listed.  So it is working
somehow.  I suspect that maybe a path to glib-networking or similar is
missing.


Kind regards
Simon