Bug#861652: task-kde-desktop: Speed of the mouse pointer does not depend on the speed settings in the system settings of the kde.

[Igor <igor@negora.com>]

I've been searching for more information about this bug, and I've found
a bug report at RedHat that probably is connected to this one:
https://bugzilla.redhat.com/show_bug.cgi?id=1227522 . This had led me to
another bug report, this time, in KDE:
https://bugs.kde.org/show_bug.cgi?id=350688 .

So it seems to be an upstream bug between KDE Plasma and LibInput. As
a workaround, one can use the "xinput" command to set the acceleration
directly from the command line:

  xinput set-prop <device_id> 276 <value>

276 is the ID of the property "libinput Accel Speed". For example, in my
case, to set the acceleration to the maximum (1.0), I've had to do this:

  xinput set-prop 12 276 1.0

Use this command to list the connected devices:

  xinput list

Use this command to know the current properties of a specific device:

  xinput list-props <device_id>

Another workaround is to just install "xserver-xorg-input-evdev" and
uninstall "xserver-xorg-input-libinput". In my opinion, for now, EvDev
suits my needs much better than LibInput.

Salutes.