Hi!

I upgrade Leap 15.4 from Leap 15.3 in a laptop (Lenovo) and when system was
running with the upgrade I lost the touchpad setting that let the user emule
the central button tapping with two fingers. When I run System Settings
(Plasma) and select "touchpad" in "input devices", change Two fingers for
tapping as middle button is disabled (both options, right or middle are
disabled.

Run Plasma as a new user or run Plasma with kwin_wayland solved (by now at
least) the issue.

Pass to reproduce:
1. Run the upgrade. Reboot in Plasma (X11).
2. Two fingers tapping is right mouse button.
3. Settings in systemsettings5 to change this are disabled.

Workarounds:
Both of follow works:
a) 
1. Create a new user.
2. Start Plasma.
3. Close session and init session as the right user.
4. Two fingers tapping as middle button works.

b) 
1. Init session with kwin_wayland
2. Use systemsettings5 to set the propper options to use tapping in the
touchpad.
3. Close session and start session with kwin_X11
4. Two fingers tapping as middle button works.

Thandks!!