Yes, I experience this routinely. As do many other people at my company.

In particular it happens when attaching external monitors while the screen is locked. There's a flash of the unlocked desktop.

I am guessing this is because the screen lock is an application drawing over top of the monitor, like XScreensaver on Linux does. A more secure-by-default architecture would have screen locking built into the display server at some lower level: If the screen is not unlocked, it will not allow the data to be passed to the GPU. It's easy for me to arm-chair architect though.

There was one guy on reddit who had a scare when his computer flashed a picture of a dead person when shutting down, and he thought his computer was haunted. It turned out to be a frame from a youtube video he was watching earlier. It may be that macOS is not that good at clearing out GPU memory sometimes.

I have the exact opposite problem. When I reboot after system updates, half a dozen YouTube videos in Chrome tabs start playing over each other on the password screen. They get through about 20 seconds before I can stop the last of them.

Audio only on the password screen, but all audible.

I’ve long had a similar problem on iOS. Whenever I return to an app, I briefly see an image from a few minutes ago. Which can be bad if I’m showing the phone to someone that old state was exposing sensitive data.

I used to see this regularly but haven't noticed it in a long while. I always assumed they were doing something like a double-buffering type trick and switching framebuffers before wiping stale content from the destination.

Apple claims, falsely, that their Operating System is "secure by design". (See https://www.apple.com/business/resources/docs/iOS_Security_O... )

This is an outright lie.

However, I'm not sure a typical iOS user cares.