The public Castor tool uses Chrome to locate video streams on webpages and sends them to a TV, converting them with FFmpeg when needed. Because it does not mirror the whole PC screen, users can continue other work and can move media processing to a NAS. The directly inspected repository says DLNA was tested on a Samsung TV, while Chromecast and Roku remain experimental without real-device validation. Automatic discovery does not cross subnets, and dependencies include Chrome and FFmpeg 7.1 or later. Castor supplies no content and rejects DRM streams, so it is not a universal service for playing every web video.