Cannot edit Night Color settings

[saxyomega90125]

I recently installed Kubuntu to a new desktop build. I set up night color with a custom time, 2330 to 0740. Color temp I set to 1000K without realizing how ridiculous that would end up being. Night Color just enabled itself at 2330 as it was supposed to, but when I went to change the color temperature, I found that it will not register a settings change to any parameter. The Apply option stays greyed out no matter what I change, and if I hit OK to close, nothing actually happens and I can reopen Night Color and find it has reset to the previous settings.
I am still able to turn off Night Color using the system tray on my panel, but that is the only control I have over it right now.
I have already restarted my system, and that did not solve the problem.

Any suggestions?

[saxyomega90125]

I've tried to edit the settings again now that I am outside of Night Color's hours, and still the same problem. Even if I hit Defaults, the Apply button stays greyed out and nothing changes when I switch tabs or close the window.
I also checked and I can apply changes to other display settings, but the Night Color menu still refuses to budge.
This is freaking bizarre - I just edited the settings yesterday afternoon without any issues.

[jlittle]

I suggest adding a new user, logging in as that user, making a note of the time by running "touch ts1" in a konsole, and checking for trouble with the night mode setting.

If you can change the setting, run "find . -newer ts1" in the konsole. This might identify the configuration file where the setting is stored, usually in the .config directory. Having a look in that file back in your original user might reveal the trouble, as might comparing the file between the users. Renaming it might fix the problem at the cost of losing some other settings.

[saxyomega90125]

Thank you very much! Finding the config using your method was straightforward - the Night Mode settings are all in /home/yourusernamehere/.config/kwinrc , for anyone who might read this in the future (for example me, after forgetting where it is) - and I was able to manually edit it without even needing root privileges. After signing out and back in, I am still unable to effect any changes to Night Color settings through the System Settings GUI, but the new settings in the config took and it is now working as I would like. I am no stranger to config files, so I can live with that.
I didn't find any suspicious info in that file. I did delete fields for [TabBox] and [org.kde.decoration2], which appeared to contain some theme-related info or settings (all to do with Breeze) but were not present in the new user's copy of the config. That seems to have done nothing at all, but I kept a backup of my previous iteration just in case.

While I was doing the check as you suggested though, something very interesting happened. I was able in the new user to change the Night Color settings, so I poked around wrapped up. When I came back and signed in again to the new user, that account was also unable to change the Night Color settings. Same exact bug.
It appears that for whatever reason, in my case the Night Color GUI is effectively one-time use!
After running 'find . -newer ts1' again, I saw that three files had been modified: ~/.local/share/baloo/index , ~/.local/share/baloo/index-lock , and ~/.xsession-errors . I have no idea what baloo is, but the third entry is quite interesting. I'm tired and unfortunately copying those files did not occur to me until after I deleted the user, but I will try tomorrow to recreate the issue and attach those things to a report to kdebugs. I do have a .xsession-errors file in my actual user, so there is that at least.

[jlittle]

Baloo is the file search indexer, which runs every minute or so.

It often gives trouble, and severe trouble sometimes. I've ranted about it. That you've noticed it running makes me suspect it's in one of its failure modes; I suggest looking in .local/baloo to see if the index is a reasonable size. Unless you have many GB of text files, or similar documents, the index should only be 10 or 20 MB. If it's more than that. or you notice it running often (it should be idle most of the time) I suggest clearing out the directory. The next time it runs it will rebuild the index and usually behaves for a while.

[jlittle]

.xsession-errors gets the text output of most programs not running in a terminal. There's all sorts of junk warnings and errors all of the time. (I wish GUI programmers were less sloppy, but maybe that's part of why I'm not one.) Conceivably you might find a clue to your problem there, but that's very rare IME.