Once in a while when waking my MacBook Air (from being off the charger and closed to open), I see a weird paint screen flash for a second (probably less then that). It kinda resembles that paint like-screen they show off on the iPhone XS (I don't think there is a connection between the two, but I say this so you can get a example of what it looks like). It also goes away like a screensaver, it like pops out and goes to the lock screen. (when you wake from a screensaver, that motion is what it kinda looks like when it goes away).
What is this that I keep seeing?