SUMMARY Not sure if bug of RFE (depends on the specified behaviour of kscreen-doctor, but I cannot find a detailed documentation). When using kscreen-doctor to eg. activate a secondary screen, that setting persists after logging out then back into Plasma. While this persistence makes sense for the GUI because most people will just set up things once and for all, it is not desirable for people who use a secondary screen only under certain circumstances, as it requires them to switch back to their default setting when logging out. Changing the "live setting" and saving some setting to be used for future sessions should be different operations. STEPS TO REPRODUCE 1. Log into session. 2. Issue kscreen-doctor output.$secondaryMonitor.enable 3. (do some work that uses the second monitor) 4. Log out / restart computer. 5. Log in. OBSERVED RESULT Plasma starts with the secondary monitor activated (and, in my case, this leads to glitches, but that is another story). EXPECTED RESULT Plasma should start with the "default" setting that was set up using the GUI. SOFTWARE/OS VERSIONS Operating System: Kubuntu 22.04 KDE Plasma Version: 5.27.10 KDE Frameworks Version: 5.104.0 Qt Version: 5.15.3 Kernel Version: 5.15.0-100-generic (64-bit) Graphics Platform: X11 Processors: 8 × Intel® Xeon® CPU E3-1245 v5 @ 3.50GHz Memory: 15.5 Gio of RAM Graphics Processor: NVIDIA GeForce GTX 1650/PCIe/SSE2 ADDITIONAL INFORMATION To preserve present behaviour, it would be possible to add a --temporary flag to kscreen-doctor to mean that the setting should be changed just for now, but not be persistent across sessions. A save-current operation could be added as well to persistently save the current configuration (that might have been set up with --temporary).
All output config changes are persistent by design, sorry. If you want to have a quick way of turning on and off the second screen, try the OSD (Meta+P) or bind the relevant kscreen-doctor commands to do it to keyboard shortcuts of your own