It's likely caused by the kernel. You should have some older kernel versions installed, but if not, you can install them via 'apt install linux-image-4.15.0-NN-generic' where NN is a number.
18.04 released with -20 (I think..), so pick something after that and 'bisect' these builds until you find the first version where it broke. Remember to select the correct kernel from the boot menu. It should be fairly easy to spot the offending commit in a specific kernel update. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1827407 Title: Touchpad scrolling becomes glitchy or unresponsive To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xinput/+bug/1827407/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs