Nothing is visible when "Maximize on Play"

1. What happened
Scene objects are not visible when using "Maximize on Play"
This did not happen in previous 5.1 build

2. How we can reproduce it using the example you attached
Create a new Project and Scene
Create a new object (or load any scene)
Click the Play button and notice that the object is visible in the Game view.
Enable the "Maximize on Play" option in the Game window... Click Play.
Note that the object is no longer visible in the Game view (bad).

After undocking the Game window, the object becomes invisible, even when "Maximize on Play" is disabled.

Note: Changing the camera's "Clear Flags" to anything other than Skybox makes the object temporarily visible.