Dots on my Login Screen

Try changing the picture in the Users & Groups System Settings. Does the issue occur with a different picture? If not, then it appears the picture has become corrupt. If the issue occurs with the other picture, then maybe try reinstalling macOS over top of itself.

CarolWolf wrote:

I have downloaded the MacOS Ventura on my computer. After some days appears some dots in the icon. What should I do?

https://discussions.apple.com/content/attachment/008c8291-f7a9-40c9-8eff-21d273598bce

And what happens when you login...???

If no issue, you can ignore the glitch or try a SafeBoot How to use safe mode on your Mac - Apple Support will sort many anomalies

The current stable release of Ventura including bug fixes, security updates is macOS Ventura 13.2.1

Keep your Mac up to date - Apple Support

Keep your Mac up to date - Apple Support

My own related thread is here .. https://discussions.apple.com/thread/254646251

I must revisit my own recommendation.  The dots, squares, reappeared on the image several days later even after having disabled bluetooth.  No longer understanding this situation, I decided to do a back up and do a complete reinstall.  Having done this I have chosen to restore Monterey. My own data use at the time was limited.  You may wish to first take the previously offered suggestion of doing a reinstall over the existing installation.  That would probably be the safer and easier option.  There would be no need to download any updates first, as I suspect the update would be included in the reinstall build itself.  If it were not, the option of updating subsequent to the reinstall would most likely be available.

I had this same problem and was able to resolve it by disabling Bluetooth. I was not aware that Bluetooth was enabled but it was. Disabling Bluetooth cleared the boxes from the user picture on the login screen.

Does it happen when you start in safe mode?

Start up your Mac in safe mode - Apple Support