I'm a relatively new Linux user having just switched from Windows 22H2 over to Fedora 39 KDE Desktop spin several months ago. My chosen Graphics Platform is Wayland. My problem is, Calibre E-book Editor has the GUI option of undocking two sub-window panes (which I accidentally did while exploring the application) and I cannot figure out how to re-dock them within Wayland.

I tried switching to X11 to re-dock the undocked sub-windows, and even though I was successful in redocking the undocked sub-windows, they re-undock themselves after switching back to Wayland. I even tried double-clicking on the two sub-windows I wish to re-dock to the main Calibre E-book Editor window, but all that does is maximize the sub-window I double-clicked the title bar of.

STEPS TO REPRODUCE:
      1. From within ebook-editor (Calibre E-book Editor), click on the undock button at the docked window pane.
      2. Double-click undocked sub-window.

OBSERVED RESULT:
      Undocked sub-window fails to redock when the Graphics Platform is set to Wayland.

EXPECTED RESULT:
       Sub-window should redock to the main Calibre E-book Editor window when the Graphics Platform is set to Wayland.


About switching back and forth to and from Wayland and X11, there exists yet another problem: Even though I'm able to successfully switching from Wayland to X11, switching from X11 back to Wayland however requires a reboot otherwise the set SDDM causes the screen to go completely black which then requires me to force me to shutdown my laptop in order to reboot it.

STEPS TO REPRODUCE:
      1. From with KDE's Application Launcher, click on "Leave", then click on "Log Out".
      2. From within the SDDM that appears, click on "Desktop session" to the bottom-left, then click on "Wayland".

OBSERVED RESULT:
      Setting the desktop session from X11 to Wayland produces a black screen.

EXPECTED RESULT:
       Setting the desktop session from X11 to Wayland should bring up the Linux desktop.


I also wish to report a third problem I just encountered. If there's only 1 user using the same computer, whether it's a Desktop PC or a laptop, and that user attempts to switch users through KDE' Application Launcher, a black screen appears where the SDDM should.

STEPS TO REPRODUCE:
      1. From with KDE's Application Launcher, click on "Leave", then click on "Switch User".

OBSERVED RESULT:
      A black screen appears in place of the SDDM.

EXPECTED RESULT:
       The SDDM should appear as normal.


As of this writing, my current system specs is as follows:

      Operating System: Fedora Linux 39
      KDE Plasma Version: 5.27.10
      KDE Frameworks Version: 5.113.0
      Qt Version: 5.15.12
      Kernel Version: 6.7.4-200.fc39.x86_64 (64-bit)
      Graphics Platform: Wayland
      Processors: 4 × Intel® Core™ i3-7100U CPU @ 2.40GHz
      Memory: 15.4 GiB of RAM
      Graphics Processor: Mesa Intel® HD Graphics 620

      Mesa version: 23.3.5

I'm unable to find out what's the installed Wayland version is, unfortunately.