Buster/lightdm - after locking screen, unlock prompt not visible

[Raj Kiran Grandhi <grajkiran@gmail.com>]

Hi,

In a fresh install of Buster with XFCE desktop, locking the screen
blanks the monitor and the monitor enters a power save state. After
that, neither moving the mouse nor typing on the keyboard would turn
the monitor back on.

Typing the password without any visual feedback (while the monitor
continues to be in the power save state) unlocks the screen and my
session is displayed normally.

Also, switching to another VT when the monitor turns off and switching
back displays the unlock prompt normally.

The closest I could find online was this:
https://bbs.archlinux.org/viewtopic.php?id=240200 wherein installing
the nouveau video driver appeared to have fixed the issue. However,
that solution is not applicable in my case as I have an integrated
intel graphics controller.

Is anybody else experiencing this bug? Any workaround?

Thanks,
Raj Kiran