Hello.
I've faced the new troubles on the all laptops with latest KDE Neon.
After suspending some elements are black: .
neither kwin restarting nor plasmashell restarting fix this.

Plasma 5.19.4
Nvidia 450.57

Has anybody ideas?
Thanks!

I don't have a laptop with linux on it but I would assume that Neon is missing something important relevant to laptops only, at the ubuntu OS level. So I would try kubuntu on one of them and if it works and you must have Neon you should be able to find out from ubuntu / kubuntu what is missing in Neon.