I have noticed that redshift does not work anymore on my machine with Linux Mint 21.3. I am sure that about half a year ago it was still working (that could be under Linux Mint 21.2 though). Trying to debug this, I found out that the problem must be with geoclue:
$ redshift
Trying location provider `geoclue2'...
Using provider `geoclue2'.
Could not connect to wayland display, exiting.
Failed to start adjustment method wayland.
Trying next method...
Using method `randr'.
Waiting for initial location to become available...
^Cpoll: Interrupted system call
Unable to get location from provider.
(I do not know why it talks about wayland, it is not a wayland session.)
Executing /usr/libexec/geoclue-2.0/demos/where-am-i from geoclue-2-demo package just times out after a while without any output or error. (Sometimes it did produce some error message about something missing IIRC, but I could not reproduce it reliably.)
Here is the status of geoclue.service:
$ systemctl status geoclue.service | cat
● geoclue.service - Location Lookup Service
Loaded: loaded (/lib/systemd/system/geoclue.service; static)
Active: active (running) since Sat 2024-06-15 13:53:51 CEST; 7min ago
Main PID: 2434 (geoclue)
Tasks: 4 (limit: 18810)
Memory: 19.1M
CPU: 424ms
CGroup: /system.slice/geoclue.service
└─2434 /usr/libexec/geoclue
Jun 15 13:53:51 Alexey-InfinityBook-Mint systemd[1]: Started Location Lookup Service.
Jun 15 13:54:12 Alexey-InfinityBook-Mint geoclue[2434]: Failed to query location: Not Found
Jun 15 13:54:17 Alexey-InfinityBook-Mint geoclue[2434]: Failed to query location: Not Found
[...]
Googling "geoclue.service Failed to query location Not Found" did not return anything relevant on the top of the search results.
I have the same problem (at least it looks the same) under LMDE 6 (Linux Mint Debian Edition).
Any help will be appreciated.