- A video card plays its video muted while the pointer is on it, or while in view when Settings -> Video covers says always play (the model covers' rule). The <video> exists only while playing, so a page of videos decodes nothing at rest; it lets clicks and drags through. - The viewer sizes a video to the window (keeping its shape): 480p outputs looked small. - Double-click in the viewer toggles full screen (checked afterwards so a browser that does it natively does not toggle twice). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>