There is the following error message from geoclue in system log:
Apr 09 21:24:33 fmn geoclue[13261]: unable to create file '/var/lib/srvGeoClue/.cache/dconf/user': Read-only file system.  dconf will not work properly.
Apr 09 21:24:33 fmn geoclue[13261]: unable to create file '/var/lib/srvGeoClue/.cache/dconf/user': Read-only file system.  dconf will not work properly.
Apr 09 21:24:33 fmn geoclue[13261]: unable to create file '/var/lib/srvGeoClue/.cache/dconf/user': Read-only file system.  dconf will not work properly.
...

Something is trying to create a file in the daemon's $HOME but since upstream commit 0f64cd1a2e80 ("Lock down systemd service file") Systemd arranges things in the way that it's not possible. I'm not sure about the error severity but allowing geoclue to write into its $HOME helps to eliminate the message.

diff -up /usr/lib/systemd/system/geoclue.service.orig /usr/lib/systemd/system/geoclue.service
--- /usr/lib/systemd/system/geoclue.service.orig	2020-04-09 21:32:25.076376400 +0200
+++ /usr/lib/systemd/system/geoclue.service	2020-04-09 21:34:18.944332678 +0200
@@ -9,6 +9,7 @@ ExecStart=/usr/lib/geoclue
 
 # Filesystem lockdown
 ProtectSystem=strict
+ReadWritePaths=/var/lib/srvGeoClue
 ProtectKernelTunables=true
 ProtectControlGroups=true
 ProtectHome=true

The replication procedure for this bug is somewhat complicated and involves making the NMEA network source up and running. Instructions for configuring a NMEA source are at https://github.com/OpenOrienteering/mapper/issues/1569#issuecomment-611442924 .