If you have two windows, each with different scene, the render output for a window would go to the other, if it was already drawing a render for the other scene. Now you can have renders draw correct in two windows for two scenes.
If you have two windows, each with different scene, the render output for a window would go to the other, if it was already drawing a render for the other scene. Now you can have renders draw correct in two windows for two scenes.