Background video gets cropped at top

How can I make background videos show the full video height at full screen width?
Details: I have a little 1080p video of two people, with space above their heads.
I tried all three ways I could find to create an INSPIRO autoplay background video:
Homepage (Widgetized), Homepage (Page Builder), Full Width(Page Builder).
In each case, the top of the displayed video is cropped roughly at the nose or eyes.
I even handbrake’d it to a weird 11:9 aspect ratio (880x780), which made no change.
I did find that as I narrowed the (Firefox Developer Edition) window width to about 5/8 of my laptop screen or less, the video got taller, so show all the top of video as I expected.