There's project called Redshift-Plasmoid which adjusts and configures screen luminosity depending on your surroundings, using Redshift. Though, the project has not been updated in about 2 years. https://github.com/simgunz/redshift-plasmoid

so, I found a redshift-qt https://github.com/Chemrat/redshift-qt, packaged and leave it here:
https://launchpad.net/~hmollercl/+archive/ubuntu/redshift-qt please test.
I've added some code that were merge to git and some that are waiting https://github.com/Chemrat/redshift-qt/pull/11 after that I hope a new release will come to package that.
@tsimonq2 said he will make a repo for it in phab.

there is new redshift-qt upstream release https://github.com/Chemrat/redshift-qt/releases/tag/v0.5

Ready with the repo and initial commit https://phab.lubuntu.me/source/redshift-qt/
not sure what I need to do next.

We need to file an ITP (Intent To Package) in Debian. @tsimonq2 should be able to help with this.

This is a little late, but I've tested the PPA (https://launchpad.net/~hmollercl/+archive/ubuntu/redshift-qt) on a 19.10 box (d780) without issue and my primary system running 20.04 (d960) without issue.

I personally thought the -gtk icon on dash was easier to see; but that'd be mostly as it's familiar to me.

The icon on the 20.04 box appears as a "!" that is hard to see (my chosen settings probably a lot to do with it; Qt Style: Breeze, GTK* Themes: Adwaita, Icon theme: Oxygen, LXQt theme: Ambiance). Sorry for this slow (belated) response.

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.

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

@hmollercl,

When I refer to "no issues" I mean the icon remains readable (globe outline, red-globe etc), not a "!" or blue-box/diamond....

• 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

• REAL TESTING follows

d780 using 19.10:
apt update again only sees 0.4-1 available from your PPA so manually installed 0.5-1. Logout & login again & Redshift-qt's icon is a globe icon, Redshift information doesn't say version (@hmollercl should this be added?), with "Location: 37.91 S, 145.04 E" being Melbourne.
Original settings: Widget Qt Style: Breeze, GTK 2/3 Arc-Darker, Icons: ePapirus, LXQt theme: Ambiance.
I changed various settings (themes/styles) hitting apply looking for issues.. all LXQt themes installed were good, changed icon themes etc. No issues (no differences over prior version noticed)

d780 using 20.04: (this is a very new QA-install so will be almost pristine)
here the 5.1 version in your PPA was detected and installed? (maybe the initial d960 was just too soon after upload? this is now many hours later..). Logout and login. Location is detected as "Location: 37.92 S, 145.04 E" so it's changed but still in Melbourne. Redshift logo is outline-of-bulb (one of the 19.10 icons). Current Widget Qt Style: Breeze, GTK 2/3 Theme: Arc-Darker, Icons theme: ePapirus, LXQt Theme: Lubuntu Arc.

Cycled through all LXQt themes (with apply & brief play) - no issues.
Cycled Icons theme (apply, brief play) — no issues.
Cycled through Widget style - no changes/issues detected
I selected a random set of GTK2 & GTK3 themes (not every combination) and didn't notice any changes/issues. I suspect these should have no impact on Redshift-Qt thus only tested random settings.

No issues detected on 19.10 or 20.04 on dell optiplex 780

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!)

I rebooted crapbook (I noted redshift icon on panel), full-upgrade then ran redshift-qt. I cycled through LXQt themes (with apply), Icon themes without issue this time. (I didn't touch widget/ or gtk2/3 themes), but then chose random LXQt themes & icon themes, again icons always visible.

Do you want more testing? (esp. on this horrid crapbook? to see if I can get mode details); b/c I rebooted dmesg is gone, but I'm looking thru journalctl currently

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)

@tsimonq2 do you have any news on this?