Hi
I'm on Debian Stretch but I'm not experiencing the issues you're discussing
here. However I remember to have had similar issues with Plasma 5 and Intel
drivers. As a workaround I used this /etc/X11/xorg.conf.d/20-intel.conf:
Section "Device"
Identifier "Intel Graphics"
Driver "intel"
Option "AccelMethod" "sna"
Option "TearFree" "true"
Option "DRI" "3"
EndSection
Given also the previous messages about this topic, enabling DRI3 indeed seems
to solve the problem. Anyhow, I discovered that the problem was with the i8xx
i9xx display driver, provided by the automatically installed
xserver-xorg-video-intel package, which could be not required by new hardware
as reported in the description:
This package provides the driver for the Intel i8xx and i9xx family of
chipsets [...] The use of this driver is discouraged if your hw is new
enough (ca. 2007 and newer). You can try uninstalling this driver and let
the server use it's builtin modesetting driver instead.
I tried to uninstall this package as suggested and the problem was solved:
sudo rm /etc/X11/xorg.conf.d/20-intel.conf
sudo apt purge xserver-xorg-video-intel && sudo reboot
Ciao
Francesco