Following the recent introduction of full Web Real-Time Communications to Chrome, Tuesday's update to Firefox makes it the second browser to support the plugin-free protocol.

The debut of WebRTC, as the protocol is known, in Firefox 22 (download for Windows | Mac | Linux) is no small potatoes. "Plugins are the single largest source of security and stability issues that we see," said Johnathan Nightingale, Mozilla's vice-president of engineering for Firefox.

WebRTC is planned for Firefox for Android (download), which also updated Tuesday, but it has yet to be added to the mobile browser.

On the surface, WebRTC sounds a lot like Skype. It lets you conduct voice and video calling one browser to another via its PeerConnection component, but it also lets you transfer data directly between two browsers thanks to a component called DataChannels. These were both added in Tuesday's new version of Firefox stable.

"How is it different from Skype misses the point of it," said Nightingale, who nearly bounced with enthusiasm in his seat while talking about WebRTC. "It's bigger than that. It's eight million developers who have access to the Web camera, or one of those audio remix tools, online."

Also enabled in the new Firefox is ASM.js, a Mozilla invention to improve the speed of JavaScript to the point where it almost loads as fast as native code. "ASM.js plus [JavaScript compiler] Emscripten on OdinMonkey [the new Firefox JavaScript engine] is fast," said Nightingale. So fast, he explained, that developers at the gaming company Epic were "jumping up and down," he said.

During a demonstration of ASM.js in May, I saw the code powering a first-person shooter that appeared to render in Firefox nearly as smoothly as native code on a console.

Other changes in Firefox for desktops include better WebGL performance thanks to asynchronous canvas updates, which means that your browser will use your hardware's graphics chip more efficiently; better memory management when loading images; support for the Web Notifications API, which will let Web updates appear in browser tabs; and adding a download progress indicator to the Dock icon on Macs.

Firefox for Android 22 doesn't yet have WebRTC or ASM.js support, although "eventually" both will come to the mobile browser, Nightingale said.

Screenshot by Seth Rosenblatt/CNET

Tuesday's update to Android Firefox does include the WebGL improvements, the Web Notifications API, and smaller Android tablets will now see the tablet version of the interface, as opposed to the phone version. It's not clear yet how or even if the browser differentiates between phones, tablets, and phablets, though.

Mozilla has made available the full changelogs for Firefox for desktops and Firefox for Android.