Additional Firefox updates from a development standpoint include CSS3 Flexbox being enabled by default, a Web Notifications API for creating simple notifications for web apps, and a built-in font inspector.
Mozilla unveiled the last of those features in March, showcasing how it exposes different information about the @font-faces used on a page, such as the font’s name and family, location, code and how it looks.
Developers should also benefit from OdinMonkey, an asm.js optimisation module for Firefox’s JavaScript engine, which Mozilla claims “allows developers to deliver gaming performance that rivals native speeds without the need for plug-ins and enables developers to create visually compelling and fast gaming experiences on the web”. Mozilla has been making a play for online gaming over recent months, as shown by its report about
Unreal's Firefox debut.