Comment # 8 on bug 1098392 from Achim Gratz

This can not be related to VirtualBox (although that might be a good way to
reproduce the bug), I have the exact same problem on bare iron (a Dell T20). 
Going back to kernel version 4.16.12-3 fixes the problem, so it can't be a
problem in libinput alone, either.

The Xorg log on the working configuration shows this:

[    17.501] (II) event0  - AT Translated Set 2 keyboard: is tagged by udev as:
Keyboard
[    17.501] (II) event0  - AT Translated Set 2 keyboard: device is a keyboard
[    17.502] (II) config/udev: Adding input device ImExPS/2 Logitech Explorer
Mouse (/dev/input/event1)
[    17.502] (**) ImExPS/2 Logitech Explorer Mouse: Applying InputClass "evdev
pointer catchall"
[    17.502] (**) ImExPS/2 Logitech Explorer Mouse: Applying InputClass "evdev
pointer catchall"
[    17.502] (**) ImExPS/2 Logitech Explorer Mouse: Applying InputClass
"libinput pointer catchall"
[    17.502] (II) Using input driver 'libinput' for 'ImExPS/2 Logitech Explorer
Mouse'
[    17.502] (**) ImExPS/2 Logitech Explorer Mouse: always reports core events
[    17.502] (**) Option "Device" "/dev/input/event1"
[    17.502] (**) Option "_source" "server/udev"
[    17.503] (II) event1  - ImExPS/2 Logitech Explorer Mouse: is tagged by udev
as: Mouse
[    17.503] (II) event1  - ImExPS/2 Logitech Explorer Mouse: device is a
pointer
[    17.503] (II) event1  - ImExPS/2 Logitech Explorer Mouse: device removed
[    17.544] (**) Option "config_info"
"udev:/sys/devices/platform/i8042/serio1/input/input2/event1"
[    17.544] (II) XINPUT: Adding extended input device "ImExPS/2 Logitech
Explorer Mouse" (type: MOUSE, id 11)
[    17.544] (**) Option "AccelerationScheme" "none"
[    17.544] (**) ImExPS/2 Logitech Explorer Mouse: (accel) selected scheme
none/0
[    17.544] (**) ImExPS/2 Logitech Explorer Mouse: (accel) acceleration
factor: 2.000
[    17.544] (**) ImExPS/2 Logitech Explorer Mouse: (accel) acceleration
threshold: 4
[    17.545] (II) event1  - ImExPS/2 Logitech Explorer Mouse: is tagged by udev
as: Mouse
[    17.545] (II) event1  - ImExPS/2 Logitech Explorer Mouse: device is a
pointer
[    17.546] (II) config/udev: Adding input device ImExPS/2 Logitech Explorer
Mouse (/dev/input/mouse0)