Hello
I have been struggling with the problems indicated in #870641 for
some time in relation to desktop machines - after locking the
screen refuses to wake up again. I believe I have discovered the
solution, through chance as much as anything else, and I expect it
will also work with the laptops.
I'm running :
Dell Optiplex 7040 with Intel HD 530 onboard graphics
Debian 10
kernel 4.19.0-12-amd64
xfce4 4.12.5
Xorg 1:7.7+19
Asus PA328 4k monitor
My particular problem was when the screen locked I couldn't wake
it up again. Some tricks worked, like typing in the dark sometimes
woke it up, or ctrl-alt-F1/F7/F8 etc etc but nothing actually
solved the issue.
Explanation and solution
What appears to be happening is that when you install Debian 10
it automatically installs a set of driver packages including xserver-xorg-video-intel
(presumably if you have Intel graphics) In the package description
it reads (and I'm translating from French so your version may be
slightly different) :
"Use of this driver is not recommended if the version of your hardware is recent (from about 2007). It is possible to uninstall this driver and let the server use its own integrated modesetting driver".