When a user clicks a Stream (on SP) video to play it in the Highlighted Content web part, they are jumped to the document library where the player loads. This is weird behavior. They have two ways to exit: 1. the back button (unintuitive); 2. click the X in the upper-right corner of the document preview UI. The latter option dumps them back to the document library rather than the SP page where they started. The old Stream web part played the video directly on-page, in the web part, via its own lightbox overlay, and this is the preferred and expected behavior. This really needs to be replicated with new Stream in the HC web part.