xkill:tldr:b6adb
xkill: Display a cursor to kill a window when pressing the left mouse button (press any other mouse button to cancel).
$ xkill
try on your machine
The xkill command is used in X Window System to force the termination of a graphical application or program. Essentially, it allows you to kill a misbehaving or unresponsive graphical application by clicking on its window.
When you execute xkill in a terminal or run dialog, your mouse cursor will turn into an "X" symbol. By clicking on the window of the application you want to close, the command will send a termination signal to that specific window or application, forcing it to close immediately.
Be cautious when using this command because it does not prompt for confirmation before killing the application, and it terminates it abruptly without giving it a chance to save any unsaved work.
This explanation was created by an AI. In most cases those are correct. But please always be careful and
never run a command you are not sure if it is safe.