Bug 443458

SUMMARY

My setup is two monitors.

One monitor is setup through a KVM switch, so I can switch between two computers on that one monitor.

By default, System Settings->Startup and Shutdown->Background Services has Startup Services/KScreen 2 running. KScreen 2 allows KDE to reconfigure the desktop screens, as necessary, whenever a monitor is added or disconnected, a very handy feature.

In my situation, I do not want KScreen 2 to do what it does normally, as whenever I switch the KVM to the other computer, the main computer will reconfigure the desktop to a single monitor. By disabling KScreen 2, I can use the KVM switch to peek at the other computer screen without disruption of the monitors or desktops. This has been working well... with one exception...

On the taskbar, there's a mini representation of the desktop, Virtual Desktop, which in two monitor mode, shows it as a wide desktop over two monitors, as expected, BUT whenever I use the KVM switch to peek at the other computer, the mini representation of the desktop squishes back to a single desktop on one monitor, even though KScreen 2 isn't running.

There is still something in the interface that is triggering the mini desktop representation to update, even without it actually updating, as I am not using KScreen 2 and have a fixed desktop config of two monitors. Could it be that there's something in the background with KScreen 2 triggering the Virtual Desktop update?

STEPS TO REPRODUCE
1. Turn off KScreen 2 on dual monitor setup and configure for one wide desktop across two monitors
2. Switch input for one monitor to another computer

OBSERVED RESULT

Virtual Desktop on Taskbar halves

EXPECTED RESULT

Virtual Desktop on Taskbar is unchanged

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: openSUSE Leap 15.2
(available in About System)
KDE Plasma Version: 5.18.6
KDE Frameworks Version: 5.71.0
Qt Version: 5.12.7

ADDITIONAL INFORMATION

Maybe it's a taskbar issue? But where to report that?