Mozilla has just released Firefox 38. With it comes the controversial Adobe Primetime DRM implementation through the W3C's Encrypted Media Extensions (EME). Or, maybe not. If you upgrade the browser through one of the default channels, the Adobe Primetime Content Decryption Module will appear in the Plugins tab of your Add-ons manager on Windows Vista or later (but it might take a few minutes after the upgrade).
Alternatively, you can use Mozilla's EME-free installer for Firefox and avoid it altogether.
I have mentioned my concerns about DRM in the past. EME does not particularly bother me, because it is just a plugin architecture, but the fundamental concept does. Simply put, copy protection does very little good and a whole lot of bad. If your movie is leaked before it is legally available in consumer's hands, as it regularly does, then what do you expect to accomplish after the fact? It takes one instance to be copied infinitely, and that often comes from the film company's own supply chain, not their customers. Moreover, it is found to reduce sales and hurt customer experience (above and beyond the valid ideological concerns).
Beyond the DRM inclusion, several new features were added. One of the more interesting ones is BroadcastChannel API. This standard allows a web application to share data between “contexts” that have the same “user agent and origin”. In other words, it must be on the same browser and using the same app (even secondary instances of it). This will allow sites to do multi-monitor split screen, which is useful for games and utilities.
WebRTC has also been upgraded with multistream and renegotiation. Even though the general public thinks of WebRTC as a webcam and voice chat standard, it actually allows arbitrary data channels. For example, “BananaBread” is a first person shooter that used WebRTC to synchronize multiplayer state. Character and projectile position is very much not webcam or audio data, but WebRTC doesn't care.