How to reproduce

1. Put a bed down facing east or west.
2. Sleep.
3. Pay attention to the color of the sky and the position of the sun and moon. They remain the way they were when you went to bed, but only for part of a second, and then update.

This works best if you sleep facing the sun or moon so that they're in your vision when you go to bed.

I was able to produce this in a normal survival singleplayer world, as well as a creative superflat world.