Safari Zoom In Keyboard Shortcut Does Not Work

Have you restarted your Mac lately?

Rebooting is the best first step in troubleshooting.

If a simple reboot of your Mac doesn’t fix things, see if the problem still happens in safe mode.  Safe mode will often correct weird software behavior by forcing the OS to clear caches, do disk repair and other self-maintenance and housekeeping and temporarily disables third-party mods.

How to use safe mode on your Mac - Apple Support 

Does the same thing happen while in Safe mode?

You can exit safe mode by restarting your Mac normally, then reevaluate the problem.

Hi,

It's working on my Mac Pro with Magic Keyboard. Sorry I don't have MacBook Pro...

You can also use a pinch-to-zoom gesture on a trackpad, can't you?