Video player creates internal margins when resized

Browser: Chromium 57.0.2987.133, Chrome 54.0.2840.99 m, Win 7 x64

When the video player element is resized by resizing the page it creates margins at the top and bottom of the video. Those margin stay there even when switched to fullscreen. This happens on the main page, video page and in a video embed on QLCrew.