I assume the device in question is the 'SYNAPTICS Synaptics Large Touch Screen'. The log file in comment #56 shows that xserver-xorg-input- libinput is aware of the device but not using it.
It also looks like you have a Xorg config file that is trying to configure that device so that config file might be the problem. Please try removing any Xorg config files you have created. ** Package changed: gnome-shell (Ubuntu) => xserver-xorg-input-libinput (Ubuntu) ** Also affects: libinput (Ubuntu) Importance: Undecided Status: New ** Changed in: libinput (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1886912 Title: DELL M3800 Touchscreen not working after login with fractional scaling. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libinput/+bug/1886912/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs