Screen glitch on startup after OS upgrade

Started 4 months ago | Questions thread
LarryRC Senior Member • Posts: 1,047
Re: Screen glitch on startup after OS upgrade

Lettermanian wrote:

Yesterday I upgraded (🤔) my 2014 MacBook Pro 13" to Big Sur from Catalina, preparing to sell this older MacBook. Now on startup, I'm getting a very brief screen glitch, happening just before the progress bar gets to the halfway point. The glitch lasts for about 1/2 second, then the progress bar speedily finishes and opens the home page as per normal this wasn't happening with Catalina. Things I tried:

- ran diagnostics (start then hold down "D" key). No issues found.

- reset SMC

-reset PRAM

- ran disk utility and first aid

- now re-installing Big Sur.

Any idea of what might be happening? Photos below. Pay no attention the man behind the screen... 😁

Just before the brief glitch

Glitch. After this the start process finishes quickly. There are no hints of anything wrong with the screen in normal operation.

maybe ignore it?

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