Hello,
I just installed my Thinkpad T510i with the actual KDE Neon, and I am pleased. It's fast, looks nice, and most settings work fine. That is...

until I closed the lid of the laptop. It has a setting to go into standby when the lid is closed, and that's what it does. But it does not wake up when the lid is opened again! I have to hard shut down the laptop and start it again.

Before this I had Linux Mint on the laptop. Mint does not support KDE anymore, that was the main reason to switch to Neon. But I could at all times activate the desktop by opening the lid.

This should be a known issue. Do I need to install some additional packages? Please help.

Update:
I booted from the Neon Live DVD and the problem is there too.
I booted from the Mint Live DVD and here I can resume from suspend as it used to be with my old installation.
So there is a configuration difference in the two distributions that cause this problem. What can I do to find out what must be configured in Neon to make it work?

In the meantime I configured the laptop to go to the login screen when the lid is closed. That works so far.

Alright after reading several messages of similar problems, I replaced the nouveau driver by the Nvidia driver. This solved the problem.

This simple command did the trick:

$ sudo ubuntu-drivers autoinstall

Here are more hints:
https://linuxconfig.org/how-to-install-the-nvidia-drivers-on-ubuntu-18-04-bionic-beaver-linux