This feature is already available in Firefox Nightly, a pre-release version of Mozilla's browser, and has very limited availability in Servo, browser engine made by individual developers and sponsored by Mozilla.
WebVR transforms VR into a first-class experience on the web, giving it the infinite possibilities found in the openness and interoperability of the Web Platform.
WebVR has been ramping up in development for several years now. Microsoft is working on bringing support to its Edge Browser and Google has an experimental version of Chrome for Windows with WebVR.
WebVR is crucial for Mozilla, as the non-profit organization is looking to bounce back from its lows and prove its relevance.
Firefox 55 is going to receive another new feature called Screenshots. "Firefox users with an HTC Vive or Oculus Rift headset will be able to experience VR content on the web and can explore some exciting demos". Mozilla explains, "With Firefox Screenshots, you can easily capture an element on screen, an arbitrary region, the visible page, or the complete page including parts scrolled off screen".
Restoring browsing sessions with a high number of tabs now takes only an instant. Speed is something that will be a selling point, as even with multiple tabs, the restoration process will be quicker, and some of the pages will not even require the reloading process.