Why is this not a feature?

Some UI components are up all the time. So after having the game on for hours it starts to burn those images in on screen. When you get used to a setup you like and have to change it all around just to avoid this it is irritating.

You should be able to select what hides when out of combat and when you rollover the section it will make it appear again. Chat can appear if you get a message or if you want to type one.