Today, three months after the release of Firefox 4, we release Firefox 5, thanks to our new development cycle. Developers will be able to create richer animations using CSS3 Animations. This release comes with various improvements, performance optimization and bug fixes.
CSS Animations (check out the documentation) are a new way to create animations using CSS. Like CSS Transitions, they are efficient and run smoothly (see David Baron’s article), and the developers have a better controls over the intermediate steps (keyframes), and can now create much more complex animations.
- You can now pass an image as a parameter to createImageDatato copy its dimensions.
- setTimeout and setInterval will only be able to execute callbacks once per second in inactive tabs. This follows the behavior of requestAnimationFrame to save CPU and power consumption.
Other Bug Fixes and Performance Improvements:
- All HTML elements now have the
accessKeyattribute, as well as the
focus()methods. These are specified in the
- In order to comply with the HTML5 specification, support for the UTF-7 and UTF-32 character sets has been removed.
- When in quirks mode, empty
<map>s are no longer skipped over in favor of non-empty ones when matching. See the Gecko notes on the
<map>element for details.
- Firefox mobile on Android now supports WOFF fonts for
- WebGL no longer loads textures from domains other than the originating domain, as a security measure.
<canvas>2D drawing context now supports specifying an
ImageDataobject as the input to the
createImageData()method; this creates a new
ImageDataobject initialized with the same dimensions as the specified object, but still with all pixels preset to transparent black.
- Specifying non-finite values when adding color stops through a call to the
addColorStop()now correctly throws
toDataURL()now correctly lower-cases the specified MIME type before matching.
getImageData()now correctly accepts rectangles that extend beyond the bounds of the canvas; pixels outside the canvas are returned as transparent black.
createImageData()now handle negative arguments in accordance with the specification, by flipping the rectangle around the appropriate axis.
- Specifying non-finite values when calling
createImageData()now properly throws a
getImageData()now correctly return at least one pixel’s worth of image data if a rectangle smaller than one pixel is specified.
- Specifying a negative radius when calling
createRadialGradient()now correctly throws
- Specifying a
undefinedimage when calling
drawImage()now correctly throws a
- Specifying invalid values for
globalAlphano longer throws a
SYNTAX_ERRexception; these are now correctly silently ignored.
- Specifying invalid values when calling
arc()no longer throws an exception; these calls are now correctly silently ignored.
- Setting the value of
shadowBlurto an invalid value is now silently ignored.
- Setting the value of
scaleto an invalid value is now silently ignored.
- Support for CSS animations has been added, using the
-moz-prefix for now.
modify()method has been changed so that the “word” selection granularity no longer includes trailing spaces; this makes it more consistent across platforms and matches the behavior of WebKit’s implementation.
window.setTimeout()method now clamps to send no more than one timeout per second in inactive tabs. In addition, it now clamps nested timeouts to the smallest value allowed by the HTML5 specification: 4 ms (instead of the 10 ms it used to clamp to).
- Similarly, the
window.setInterval()method now clamps to no more than one interval per second in inactive tabs.
XMLHttpRequestnow supports the
loadendevent for progress listeners. This is sent after any transfer is finished (that is, after the
loadevent). You can use this to handle any tasks that need to be performed regardless of success or failure of a transfer.
Bloband, by extension, the
slice()method has been removed and replaced with a new, proposed syntax that makes it more consistent with
- The value of
window.navigator.languageis now determined by looking at the value of the
- Regular expressions are no longer callable as if they were functions; this change has been made in concert with the WebKit team to ensure compatibility (see WebKit bug 28285).
Function.prototype.isGenerator()method is now supported; this lets you determine if a function is a generator.
classSVG attribute can now be animated.
- The following SVG-related DOM interfaces representing lists of objects are now indexable and can be accessed like arrays; in addition, they have a
lengthproperty indicating the number of items in the lists:
- Firefox no longer sends the “Keep-Alive” HTTP header; we weren’t formatting it correctly, and it was redundant since we were also sending the
Proxy-Connection:header with the value “keep-alive” anyway.
- The HTTP transaction model has been updated to be more intelligent about reusing connections in the persistent connection pool; instead of treating the pool as a FIFO queue, Necko now attempts to sort the pool with connections with the largest congestion window (CWND) first. This can reduce the round-trip time (RTT) of HTTP transactions by avoiding the need to grow connections’ windows in many cases.
- Firefox now handles the Content-Disposition HTTP response header more effectively if both the
filename*parameters are provided; it looks through all provided names, using the
filename*parameter if one is available, even if a
filenameparameter is included first. Previously, the first matching parameter would be used, thereby preventing a more appropriate name from being used. See bug 588781 .
- Support for embellished operators
- The Web Console’s
Consoleobject now has a
debug()method, which is an alias for its
log()method; this improves compatibility with certain existing sites.
Developer Relations Team, long time jQuery contributor and Open Web enthusiast. @louis_remi