I have a Compaq 21N121AR Laptop and this is my problem: After I make a mouse movement and my finger leaves the mouse touchpad, my touchpad goes in a kind of "Sleep Mode" and it takes a few "swipes" to move again. I used the xinput list command and noticed that one of the devices dissapears (I assume it's the mouse touchpad). This is before I move my mouse, note the virtual core pointer part:
Found it! It seems to be a problem with the libinput drivers, I solved my problem removing them and installing the synaptic drivers instead
sudo apt-get remove xserver-xorg-input-libinput libinput-tools
this removes libinput drivers, and then to install synaptic drivers:
sudo apt-get install xserver-xorg-input-all xserver-xorg-input-evdev xserver-xorg-input-synaptics
And then I restarted the system and it was solved. Thanks to Jason Gambrel for posting this solution on Trackpad randomly freezes