Purple screen with vertical black dots
Its a mid 2012 13" MacBook Pro with a i5 2.5GHz processor and 4gb of RAM
Sometimes when I shut down my macbook, for a moment I see a purple screen with black dots aligned in a vertical form. I have no idea why. It boots up just Fine and I hear no weird or odd noises, though it tends to happen when lots of things are going on and the colorful windmill shows up.
Could it be a hardware problem?
MacBook Pro, macOS High Sierra (10.13.2)