Graphical window stopped working after apt update and upgrade and a reboot

Hi, I have the exact same problem with “Failed to start Light Display Manager” and dwhdmi-rockchip fdea0000.hdmi: use tmds mode in dmesg.

I have installed the two plymouth packages above and also accountsservice as I was getting: rock-5b lightdm[1197]: Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.Accounts was not provided by any .service files

However, still no X graphical screen. It did work with the initial image on the SD card. Before the kernel upgrade.

Anyone have any ideas how to fix this?

Or - what’s the easiest way to go back to the previous kernel (I am familiar with grub2, I don’t see it here).

Rock 5B. Bullseye 64-bit. 5.10.110-34-rockchip-gca15bbe36e6c

Thanks in advance.