Thanks @guiverc!!

there is a problem when no internet is found by geoclue. But that's more a redshift problem than a redshift-gtk or redshift-qt. There is no fallback. However, you can give redshift and redshift-qt manual latitude:

-l LAT:LON Your current location
I haven't take the time to see if the ppa will actually update the version, is more for testing purposes (instead of giving the .deb)

I added PPA onto 20.04 sony vaio ultrabook (i5-9400u, 4gb, intel haswell-ULT); and installed redshift-qt there (no redshift was installed). This box wasn't updated first and I started play it crashed pretty quickly (problem encountered; nothing in /var/crash/); I'd intended updating whilst I played.... I'll blame the non-upgrading first; though my internet has been flapping (no connection 6-7 times per hour for a ~minute) so maybe it wasn't getting geoclue responses?? Sorry I closed it & rebooted to start again before it occurred to me I should explore (stuck on the no full-upgrade first!)

• initial play (very early);

My main box (d960): Redshift-qt's panel icon was a blue box/diamond with a light blue icon partially visible, I no longer recall when the "!" got replaced by the blue-box sorry. I can see the package there (in browser) but sudo apt update didn't see it available so I wget & dpkg -i installed on my 20.04 primary box; I used the 'quit' option to have program quit & restarted it. It was back to "!" icon set; operation appears identical & I didn't see any differences (very short play; it'll take days to test properly with color shifting due to time). Maybe it needs a logout/login; test that later...
This is my primary box; very non-standard config & rebooted about once a week

@guiverc I just uploaded version 0.5-1 to ppa, could you test it if icons works ok?
thanks!

After some looking in the source of lxqttaskbar (part of the source for lxqt-panel), I was unable to find a function for switching to the next task. I only found the code for switching to a specific task number from 1-10 as is already implemented in Lubuntu at the end of the source code.

thanks @guiverc I think problem is that Oxygen Icon doesn't have redshift icons so fall back to whatever. I will have to revisit where should I leave the icons during installation.