Thinkpad T530 touchpad buttons remapped after sleep

[Sven Neuhaus]

This possibly the same issue as #501942 (which has been closed to inactivity).

I have noticed the following issue after upgrading from Ubuntu 16.04 to Ubuntu 18.04:

package: xserver-xorg-input-synaptics 1.9.0-1ubuntu1

After waking up from suspend, the lower left touchpad button generates "button 2" events (I checked using xev) instead of "button 1" events.

To be specific, it *sometimes* generates button 1 button release events.

The button above the touchpad still generate button 1 events as before sleep.

The issue disappeared by itself after 40 minutes or so. It has happened on multiple occasions.