black screen when connecting through vnc / X server freezes

[Francisco Leon]

This is going to be a hard one. I have been having this issue in every raspbian / raspberry pi versions i have had. I don't see this problem appearing on other distros or desktop versions so i finally decided to report this.

I have a raspberry pi 4 , 4GB with the latest raspbian (based on debian 10). I use chromium very frequently and watch videos. When i'm away i login 3-4 times a day through VNC, but almost every day i cannot get the screen to show up in VNC because all i get is a black screen. When i get back to the area with the rpi4 X appears frozen and i cannot use either a keyboard or a mouse.

SSH still works and i'm able to connect normally and the only thing that temporarily fixes this is a reboot. The reboot takes around 10-15 minutes for reasons that i don't know.

I have every apt update and i don't run beta firmware or kernel. Kernel is 4.19.66-v7l+ #1253 SMP Thu Aug 15 12:02:08 BST 2019 armv7l GNU/Linux.

Most of the time i'm running the pi headless without either a monitor, mouse or keyboard connected.

My /boot/config.txt has:

dtoverlay=vc4-fkms-v3d
max_framebuffers=2
hdmi_force_hotplug=1

libc6 version 2.28-10+rpi1
I see some potential issues in /var/log/messages (attached)

i don't know if vnc is caushing the X server crash or if it's just a coincidence, but as you can see i just connected before getting those error messages in the log 30 seconds later.

Please help, as i'm tired of having to reboot the rpi 3-4 times a day.