If keyboard shortcuts don’t work on Mac

Some keyboard shortcuts may be unavailable in some apps. Make sure you’re using the latest version of the app.
If the keyboard shortcut uses a function key, you may also need to press and hold the Fn key or the Globe key on the keyboard to perform the shortcut (depending on your Mac model, if you’re using a Magic Keyboard, and how you set an option in Keyboard settings).
If a warning icon appears next to a keyboard shortcut, another app is already using that shortcut. You can change a conflicting keyboard shortcut.

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macOS User Guide