Xperia Z5
When you spawn a wither. The sky becomes darker. But when you reload the world while the wither is there. It goes back to its normal look
Steps to reproduce
Start a creative world.
Create a Wither.
Notice that the sky changes to wither sky.
Leave the area where the wither is until the wither heath bar is no longer shown on your screen.
Reopen the world.
Notice that the sky is normal again.
Go back to where the wither is.
Notice that the sky changes back to wither sky.
I think this is possibly WAI?