I'm using Fedora KDE Plasma 5.5.0 on a 2011 macbook air. When I go to the touchpad settings the majority of the settings are unavailable to me (greyed out and can't adjust). My touch click is WAY too sensitive, so when I brush my palm against the trackpad in the wrong way it clicks away from what I'm working on. I can't turn on the palm detection, and this is likely what I need. How do I get access to these settings?

Most of the other touchpad settings are also disabled; I can only enable mouse click emulation, scrolling, speed, and disable when typing. Everything else is greyed out and deactivated.

Same here in debian 9 stretch with kde. After all this time, did you find a solution?

3 years after or so. Same thing is returned to my nice kde5 on debian 9 installation.

Maybe someone can drop any clue to see where could be some way to search in a aprox good or so direction
Thanks!

I know this is an old thread, but maybe this will help others that have had the same problem...

The problem in my case was that I was using the xf86-input-libinput driver instead of the xf86-input-synaptics. If the xf86-input-libinput is installed it takes control of the touchpad by default.

The synaptics driver is no longer under active development, but it still exposes more configuration options than libinput. After removing the libinput driver and installing the synaptic one all greyed out options were available again. (you might have to logout or reboot first, but idk for sure)