I recently upgraded to ubuntu 17.10 and since then I cannot do two finger scrolling, only edge scrolling. Any suggestions how to make the two finger scrolling work again? I use a Lenovo ThinkPad 450s
Output of xinput list-props $(xinput list | perl -ne '/touchpad.*\bid=(\d*)/i && print $1') as requested by @Hi-Angel
Device 'SynPS/2 Synaptics TouchPad': Device Enabled (141): 1 Coordinate Transformation Matrix (143): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000 libinput Tapping Enabled (276): 1 libinput Tapping Enabled Default (277): 0 libinput Tapping Drag Enabled (278): 1 libinput Tapping Drag Enabled Default (279): 1 libinput Tapping Drag Lock Enabled (280): 0 libinput Tapping Drag Lock Enabled Default (281): 0 libinput Tapping Button Mapping Enabled (282): 1, 0 libinput Tapping Button Mapping Default (283): 1, 0 libinput Accel Speed (284): 0.600000 libinput Accel Speed Default (285): 0.000000 libinput Natural Scrolling Enabled (286): 1 libinput Natural Scrolling Enabled Default (287): 0 libinput Send Events Modes Available (261): 1, 1 libinput Send Events Mode Enabled (262): 0, 0 libinput Send Events Mode Enabled Default (263): 0, 0 libinput Left Handed Enabled (288): 0 libinput Left Handed Enabled Default (289): 0 libinput Scroll Methods Available (290): 1, 1, 0 libinput Scroll Method Enabled (291): 0, 1, 0 libinput Scroll Method Enabled Default (292): 1, 0, 0 libinput Click Methods Available (293): 1, 1 libinput Click Method Enabled (294): 1, 0 libinput Click Method Enabled Default (295): 1, 0 libinput Middle Emulation Enabled (296): 0 libinput Middle Emulation Enabled Default (297): 0 libinput Disable While Typing Enabled (298): 1 libinput Disable While Typing Enabled Default (299): 1 Device Node (264): "/dev/input/event5" Device Product ID (265): 2, 7 libinput Drag Lock Buttons (300): <no items> libinput Horizontal Scroll Enabled (301): 1 02 Answers
The answer here by @hpotter40 worked for me:
$ sudo modprobe -r psmouse $ sudo modprobe psmouse This was taken from comment #16 of this bug report:
Update for a more persistent solution:
Based on comment #44 and #45 of the same bug report above, this should also work. Open the file /etc/default/grub and edit the value of the GRUB_CMDLINE_LINUX_DEFAULT variable. By default this has the value of "quiet splash". The value "psmouse.synaptics_intertouch=0" could be added to it so that it becomes like:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash psmouse.synaptics_intertouch=0" Then update GRUB by executing:
$ sudo update-grub Reboot your system and this setting should survive even after suspends. As a note, all these answers are simply workarounds until the kernel error could be identified and patched.
6You can enable two finger scroll by clicking System Settings > Mouse & Touchpad. You will see a window like this 
You can (un)check the check box according to your preference.
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