If your Vi or Vim session is hanging and is not responding to anything, then it might be because you pressed CTRL+S accidentally (out of habbit). To fix this, just press CTRL+Q to unblock the session.
If your wifi card is not available after booting your Dell XPS-15 laptop (with Ubuntu 20.04 or 22.04), or your external monitor refuses to display anything, please try the following:
start up your laptop without your power supply plugged in, connect with wifi, and/or your external monitor and only then plug in your power supply.
This fix works everytime for me.
If you press CTRL-ALT-DEL on a Ubuntu Server the server will be shut down without asking any confirmation or password. This is of course not a good idea.
To disable this, enter the following commands as root:
systemctl mask ctrl-alt-del.target systemctl daemon-reload