Very similar case now:
The two-finger scrolling does not work at all, as if not enabled. Disable and
back, reboot, power off and on ... nothing helped it.
DistroRelease: Ubuntu 18.04
Uname: Linux 4.15.0-62-generic #69-Ubuntu SMP Wed Sep 4 20:55:53 UTC 2019 x86_64
CurrentDesktop: Gnome
--
You
Addendum :
The problem started recently, after one of the last updates, since June 2019.
It is irrelevant to mouse, which works fine, including the wheel-scrolling.
The system is a P50 lenovo, and problem appears either while on docking station
or not.
--
You received this bug notification
** Changed in: software-center (Ubuntu)
Status: New = Triaged
** Changed in: software-center (Ubuntu)
Importance: Undecided = High
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1410540
** Attachment added: touchpad_settings_4.png
https://bugs.launchpad.net/ubuntu/+source/software-center/+bug/1410540/+attachment/4297935/+files/touchpad_settings_4.png
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
** Attachment added: touchpad_settings_2.png
https://bugs.launchpad.net/ubuntu/+source/software-center/+bug/1410540/+attachment/4297930/+files/touchpad_settings_2.png
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
** Attachment added: touchpad_settings_3.png
https://bugs.launchpad.net/ubuntu/+source/software-center/+bug/1410540/+attachment/4297932/+files/touchpad_settings_3.png
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
Note that, strangely, touchpad scrolling works fine when the cursor is
on the right of the screen (approximately the right quarter of the
screen).
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1410540
