From the current version 33 Firefox officially supports the proprietary and licensed video codec H.264. Which was providing through cooperation with the network specialist Cisco, the OpenH264 as a free codec plug-in possible. Since the features are not yet fully developed, it uses the browser initially only for WebRTC , the standard for video and audio chat in real time. No support is the native playback of H.264 web video with the video tag. Your cooperation agreed Mozilla and Cisco already a year ago. Cisco made ??H.264 open source , released him with an open-source license and expressly promised not to want to pass on the cost of its own MPEG-LA license for the module. Mozilla pulls completely open codec before and still support the development of alternatives such as H.264 Daala. "The Web is an open ecosystem, generally free of proprietary control and technologies - video except", Mozilla's Chief Technology Officer Andreas Gal expresses his regret in a blog post from. "Unfortunately, not a royalty-free codec won enough spread to be a serious competitor for H.264. Mozilla will continue to support the video format VP8, but we have the impression that VP8 has not been able to find enough spread to replace H.264 can. "The Firefox users is therefore best served by a video codec in WebRTC which ensures the highest possible interoperability.