Mouse focuses the game when while console is open if the window is minimized and then restored. When the console is opened the mouse is shown and the game is no longer focused (expected). However, if the standalone window is minimized and then restored the console will be open, the mouse will be shown, and the game will have focus (the camera is following the mouse (unexpected))
Result: The camera appears to follow the mouse
Expected: The camera would not follow the mouse until the console is closed and the game window is clicked
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-70259 in the post.