Reports on negative experiences are welcome, too. Any suggestions on how to smooth the transition to Wayland for those who depend on customized X11 window managers and those tools are welcome.
This looks to me DE specific so are you using KDE, Gnome or anything else? Both KDE and Gnome are pretty far on the trajectory to switch to Wayland so that should work.
For that there is ydotool and kdotool, ydotool is in the standard repo’s, kdotool is KDE specific and not in the standard repo’s, I did build it myself. I am quite sure it will fit my needs but I did not make a permanent switch yet.
See also here, what prevents me from switching is that KDE still can not remember the windows after a reboot
This is not possible. XWayland is only there for getting X Software running on Wayland. If you want to have a full WM/DE look into Wayback, as it extends Xwayland which can run these kind of things
Having used Icewm in Leap 15.6 and then migrated to Leap 16.0, I have noticed no changes in the behaviour of Icewm though I had not previously set up any keyboard shortcuts or configuration dot files. Rather I placed edited configuration files in my user directory which automatically override the equivalent ones in root.
You probably noticed no difference in the way IceWM behaved because it’s using X11 no matter what the distro or release. IceWM doesn’t support Wayland so there would be no change.
openSUSE Leap 16 installer provides only Wayland variants of desktop environments. Xorg-based environments can be installed manually post-installation.
Before using the opensuse-migration-tool I deleted all the Leap 15.6 specific repos; so during the migration I only had the two Leap 16 repos and Packman active. I have not installed any Xorg-based environments since migration.
Your hypothesis about X11 packages being left over from Leap 15 appears to be supported and it would appear that the opensuse-migration-tool took account of the presence of X11 but made the installation Leap 16 compliant because it deleted all but four of the contents of /etc/X11/ leaving xdm, xinit, xorg.conf.d and xorg.conf.install all of which have received upgrades since I migrated to Leap 16.
Note that Myrlyn lists X11 and Icewm in Patterns and Icewm as an official package presumably to assist those who want to make manual installs. These are checked in Myrlyn in my Leap 16; as I have not added any repos or done a manual install, I assume that these were checked by the opensuse-migration-tool when I migrated.
Confirming that a default Leap 16.0 install has xorg-X11-server and related packages and patterns and icewm is not installed by default but available in the oss repo.
So likely both were simply upgraded from 15.6 by the migration tool.