Hi. I had some display issues on a 3 display setup. I trouble shooted this issue by trying different combinations of displays, DP and HDMI outputs, cables etc. This lead to strange issues as KDE built up different configurations. At some point, one combination would keep one or two displays from turning on, depending on the combi. Another combination would restrict one of the screens from going higher than 800x600 resolution. I fixed all of these issues by removing the ~/.local/share/kscreen folder and rebooting. I am guessing that this is a symptom of KDE's ability to remember different screen layouts, which is fine. It took a lot of different combination attempts on my part to produce this issue. I also knew with a certainty what was the cause of this issue, but had to do some online search to locate the config folder in order to delete it. If this issue occurred to a user with limited knowledge, they would properly not be able to fix this without a re-install. Maybe there should be something in settings to reset all of the saved display configurations?
In general, adding options and features to let people work around bugs doesn't make for a great user experience. Can we re-focus on the issues that led you down the path of looking for workarounds in the first place? Can you describe those issues?
(In reply to Nate Graham from comment #1) > Can we re-focus on the issues that led you down the path of looking for > workarounds in the first place? Can you describe those issues? I can try. So I have a setup with two PC displays and a TV, all hooked up to a Radeon 580 GFX card on a Desktop PC. All 3 screens only had support for HDMI and my GFX card has two HDMI and two DP output ports, so the TV was using an HDMI/DP adaptor. It worked fine, except for the general issue that KDE has with multiple displays (still exists in Plasma 5.24 btw). Then I bought two new PC displays to replace the old ones and it worked fine as well, after replacing them and setting them up. But at some point my TV started to flicker, so I had to do some trouble shooting. At first I thought that this was due to a poor HDMI/DP adaptor, since this seamed to be the weak part of the setup. I switched the adaptor to another one that I had laying around, but now the TV only displayed a resolution of 800X600, and I could not change this. I thought that both adaptors was broken in different ways, and thought that I would go without them. The new PC displays had both HDMI and DP options, so I switched one of them to DP and removed the adaptor for the TV and plugged it in HDMI directly instead. Now one of the PC displays did not turn on no mater what I did. I tried putting everything back to the original outputs and adaptors, but now one of the displays would not go higher than 800X600. I then Removed that turned off display, and the TV got back it's resolution. I plugged the display back in, and the TV changed resolution and the display did not turn on. I now tried switching both displays to DP and again remove the adaptor for the TV. Now the TV did not turn on and one of the displays would not gain a higher resolution than 800X600. Removing the working display, turned the TV back on and fixed the resolution on the other display. I searched the web for where KDE kept it's display configs, since it was clear that something was remembered in a strange way. I found something about ~/.local/share/kscreen and deleted that. After a reboot, everything was back and I could setup all of the displays again, the way I liked it. I also found out that it was the HDMI cable from the TV that made the flickering, not the adaptor. However I now have it setup using DP to DP on the displays and HDMI to HDMI on the TV.
Sounds like you found what you needed. A GUI "reset everything" button is tracked by Bug 389568. Being able to reset only your KScreen configuration from the GUI is a bit too niche, I think. In the future, we'd like bug reports on individual issues so we can try to fix them! :)