There is a regression of this bug in Ubuntu 20.04 using the default Gnome desktop
Setup is a Shuttle POS P511
using a Weida CoolTouch controller with driver integrated into the Linux kernel
Second screen is a AOC USB-3.1 Display Link monitor without display capabilities only (no touch).
When the AOC screen is disconnected the touch works normally.
When the AOC screen is connected the touch is out of sync and touches over both screens from the Shutlle/Weida screen.
Here is xinput list-props with both screens connected.
There is a regression of this bug in Ubuntu 20.04 using the default Gnome desktop
Setup is a Shuttle POS P511
using a Weida CoolTouch controller with driver integrated into the Linux kernel
Second screen is a AOC USB-3.1 Display Link monitor without display capabilities only (no touch).
When the AOC screen is disconnected the touch works normally.
When the AOC screen is connected the touch is out of sync and touches over both screens from the Shutlle/Weida screen.
Here is xinput list-props with both screens connected.
xinput list-props 11
Device 'Weida Hi-Tech CoolTouch® System':
Device Enabled (169): 1
Coordinate Transformation Matrix (171): 0.500000, 0.000000, 0.500000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
libinput Calibration Matrix (308): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
libinput Calibration Matrix Default (309): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
libinput Send Events Modes Available (291): 1, 0
libinput Send Events Mode Enabled (292): 0, 0
libinput Send Events Mode Enabled Default (293): 0, 0
Device Node (294): "/dev/input/event4"
Device Product ID (295): 9589, 49920