Firefox changes so quickly it is difficult to keep up with what features are in development. Firefox 15 is now in beta and 16 is on its way. Let's take a look at what is on offer.
Firefox 15 is in beta and the biggest issue fix is its long standing memory leakage problems.The new version should prevent most leaks from add-ons and a decrease in memory consumption. On the same sort of topic an incremental garbage collector should also help with the problem of the browser seeming to crash because it freezes when garbage collection is initiated.
Perhaps the biggest change, although it is difficult to know how much impact it will have, is the support for the Opus audio codec. Opus is a do everything "super" codec that provides better or equal performance than alternative codecs. It can be used to compress everything from speech to high quality music using the same basic algorithm. Rather than having to choose an audio format to suit the application you can simply use Opus and tune its parameters - and yes it claims to be better than MP3, a 64kbps Opus file sounds better than a 96kbps MP3. Added to its technical advantages it is also free and an IETF standard. Its downside is that this is yet another audio format to support and not all browsers can use it. If it did catch on then it would be a huge simplification but...
Firefox 16 is more experimental and as always some features may not make it into the release. The most important change is that CSS features have dropped the Mozilla prefix. In case you haven't noticed CSS prefixes have developed into one of the biggest incompatibility and maintainability problems in developing mobile web apps. Most developers have simply opted to use webkit prefixes so destroying any hopes of browser independent code. Firefox has now dropped the prefix from Animations, Transitions, Transformations, and more. In most cases you can simply remove the prefixes and start using the CSS3 form. The exception seems to be gradients which have changed syntax from prefixed to unprefixed. There are a range of other improvements including the unprefixing of the Battery API and the Vibration API.
A new developer toolbar should make it easier to get to the tools you need. There are also minor changes to web console and the scratchpad.
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