To remove an application from a Mac's "Notification Center", click on the Apple icon → Click on "System Preferences" → Click on "Notifications" → Click on an application → Remove the check mark from the "Show in Notification Center ".
Steps
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Step 1. Click on the Apple icon
It depicts the Apple logo and is located in the upper left corner of the menu bar.
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Step 2. Click on System Preferences
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Step 3. Click on the "Notifications" icon
It looks like a gray box with a red dot in one corner.
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Step 4. Click on an application on the left side of the window
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Step 5. Click on the "Show in Notification Center" box to remove the check mark
It is located on the right side of the "Notifications" window.
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Step 6. Click on the red "x" button
The application will no longer appear in the Notification Center.