Version 55.0.1, first offered to Release channel users on August 10, 2017
Today's release brings innovative functionality, improvements to core browser performance, and more proof that we’re committed to making Firefox better than ever. New features include support for WebVR, making Firefox the first Windows desktop browser to support VR experiences. Performance changes include significantly faster startup times when restoring lots of tabs and settings that let users take greater control of our new multi-process architecture. We’ve also upgraded the address bar to make finding what you want easier, with search suggestions and the integration of our one-click search feature, and safer, by prioritizing the secure - https - version of sites when possible. Read what Nick Nguyen (VP, Firefox Product) has to say about Firefox 55, get historical perspective on the development of WebVR from Sean White (SVP, Emerging Technologies) in this Medium post, and read about all the new features for developers in Firefox 55 on Mozilla Hacks.
We'd also like to extend a special thank you to all of the new Mozillians who contributed to this release of Firefox!