Just adding a quick note that I experienced this problem on a Thinkpad T480 running 18.04, after updating to 4.15.0-62-generic. Going back to 4.15.0-55-generic fixes the issue. I didn't check -58 and -60 to see how they behave, but I should do that as soon as I have time for that. Note that it may also be a different issue with the same symptoms. This is also a SynPS/2 Synaptics device.
Just adding a quick note that I experienced this problem on a Thinkpad T480 running 18.04, after updating to 4.15.0-62-generic. Going back to 4.15.0-55-generic fixes the issue. I didn't check -58 and -60 to see how they behave, but I should do that as soon as I have time for that. Note that it may also be a different issue with the same symptoms. This is also a SynPS/2 Synaptics device.