Screen Mirroring with Sequoia (OSX 15.4) and external displays like our projector in McBryde 563 is a little more complicated then previous OSX versions. If you connect the display to your Mac and the screen on the external display is black with a message to click on some icon (Screen Mirroring), please follow these instructions.

• At the top right of your screen, please click on the icon as shown in the following image.
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• This opens the Screen Mirroring. Click the 'Choose Content' button at towards the bottom.
  
• In the next window, select to mirror the Entire Screen, Window or App, or Extended Display. Then click on the 'Start Mirroring' button at the bottom right.
  
• To stop using the external display. Click the Screen Mirroring icon in the top right then click on the 'Stop Exendending' button in towards the bottom right. *NOTE* It may have a different name if you are mirroring the entire screen or just a window.