unwanted image on log in
I get a nine-square grid on my screen when I log in. Don't know where it came from and can't seem to get rid of it.
MacBook Air 15″, macOS 14.7
Does that image appear if you boot "Safe Mode"?
Start up your Mac in safe mode - Apple Support
Might it be possible for you to capture and upload a screenshot of it?
Instructions for capturing, editing (if necessary) and posting screenshots to this site can be found in the Appendix in Writing an effective Apple Support Communities question - Apple Community. Refer to Screenshots (Mac).
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