14 DAY TRIAL // Firefox 25 is now available to all Aurora channel users, bringing a rather short list of new features and changes. The changes that interest developers aren't that many or that great either, but there are a few things to look out for.
One interesting new feature that should help with debugging quite a lot is "black boxing." Very few websites use purely native code at this point, most rely on any number of libraries. jQuery is so ubiquitous that it's basically just an extension of JavaScript at this point.
Developers use these libraries for convenience and, by design, they shouldn't have to worry about how they work internally. But when debugging your code, error or warning messages from these libraries are bundled together, making it hard to see just the ones that interest you.
With Firefox 25, you can now instruct the browser to use various source files as a black box, completely ignore breakpoints, pauses for exceptions and so on.
The newly introduced Network Manager is getting some improvements, you can now modify a request before resending it, tweaking the URL, the HTTP method, as well as the header and the body of the request itself.
Also new is support for CSS autocompletion in the inspector, so you can add or modify elements right then and there. Firefox 25 Aurora also introduces the ability to execute JavaScript code from the web console in the scope of the current pause frame rather than the global scope.
Finally, developers can import and export profiled data in the Profiler, to make it easier to share the data with others who may not be able to reproduce the exact conditions you're encountering.
As for web platform features, Firefox 25 introduces support for CSS background-attachment:local and new ECMAScript (JavaScript) 6 functions.