Mozilla today launched Firefox 35 for Windows, Mac, Linux, and Android. Major additions to the browser include room-based Firefox Hello conversations, H.264 (MP4 files) playback on OS X, and integration with the Android download manager. Mozilla has opened up the Firefox Marketplace for the desktop, currently in beta. While Firefox Marketplace is already available on Firefox OS and Firefox for Android, the company is now asking users to help test apps on Windows, Mac, and Linux. Full changelogs: desktop and Android."