I recently installed Plasma 6, and the system settings are now saying “No touchpad found” in the touchpad section. The touchpad still works, but I can’t change any settings. The update also seems to have disabled 3 finger middle click, and this means I can’t enable it. Does anyone have a fix?
KDE Neon 6.0 (Plasma 6.0.3)
X11
That sounds to me like the X11 input driver is still using synaptics or evdev for the touchpad, as opposed to libinput. Plasma 6 removed settings backends for drivers other than libinput. The synaptics driver is long unmaintained, was a technological dead end, and made any feature work on mouse & touchpad settings a giant pain. The evdev driver provides only barebone functionality and libinput builds on top of it to do a better job.
On my old Arch setup, I had to install the xf86-input-libinput package for the libinput-based X11 driver. And I also had to take out the global config file from /etc/X11/xorg.conf.d/ that assigned the synaptics driver instead of the libinput default that got assigned in the pre-installed /etc/X11/xorg.conf.d/40-libinput.conf. Not sure what the situation looks like on Neon, probably somewhat similar but a little different.
The only file I have in /etc/X11/xorg.conf.d is 00-keyboard.conf. I dont have a file for libinput.
Also what would the equivalent package be fore Ubuntu based distros? I have libinput-bin, libinput-dev, libinput10, and xserver-xorg-input-libinput already.
Remove the xserver-xorg-input-synaptics package and restart X. Libinput will then take over handling of the touchpad settings.