So, the underlying problem here is that browser chrome is loaded asynchronously, and usually, when launching an app that requests chrome, the app will load before the chrome (e.g. Facebook). When the chrome loads, it suddenly appears and the application jumps down jankily to compensate. I think it would be much nicer if this animated in, and I have two suggestions on how: 1- The space for chrome will be reserved before chrome loads - it will appear blank and the chrome will fade in. Chrome loads quite quickly, so this shouldn't look too odd. 2- Chrome slides into position from the top after it loads. This would look nicer, but would likely be harder to implement.

No point in profiling this, this isn't a performance issue - we just have no transition when we load in app chrome.

Firefox OS is not being worked on