If your application still does not close properly, open a Terminal window (located in the Applications/Utilities folder) and enter the following command:
Killall “name of your application”
Rename “name_of_your_application” with the actual application name and press "Enter."
If the name contains a space, remember to add a backslash before it. For example for “Mac OS”, you should type “Mac \ OX” (without quotes)
It is not always easy to find the application name because the name that appears is often not the real name of the application.

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