To put your browser in full screen:
On a PC, do this:
or on a Mac use this:
You can also adjust the size of each window in your video player area.
To immediately view full-screen video, click the "Fullscreen" button, located at the bottom right corner of your video viewscreen:
Another option is to click the "downward arrow" button to minimize /maximize the video window, or grab and drag the window edge / divider to manually re-size it.