Internet Explorer 9 release candidate arrives

Microsoft has pushed out the 'feature-complete' IE9 RC, with user interface and performance tweaks, for developers to test their sites

Microsoft has unveiled the release candidate of its next web browser, Internet Explorer 9, and made it available for download.

Internet Explorer 9 RC

The IE9 RC adds the ability to move tabs to a separate row. Credit: Simon Bisson

The Internet Explorer 9 (IE9) release candidate (RC), announced on Thursday at an event in San Francisco, is a developer release, explained Mark Quirk, Microsoft product manager for the browser. Like recent releases of Windows and Office, the RC is little changed from the beta version.

"What we really wanted to do was finish off the core features. It's feature-complete and allows developers to test their sites," Quirk told ZDNet UK.

Microsoft did not give a release date for the final version of IE9, though Quirk did shed some light on this. "We're not so far away from a release," he said.

IE9 RC features

New user interface features in the RC include support for 'pause' and 'resume' in IE9's download bar. In addition, the shape of tabs has changed and users are now able to move tabs from beside the combined address and search bar to a separate row.

The browser now also has a new query operator to force searches, as well as the ability to quickly go to any URL in a clipboard without the user having to paste the URL into the address bar.

The IE9 RC also includes new security and privacy features, adding tracking protection to block information about users' browsing habits from being passed to advertising networks. Microsoft will ship four tracking protection lists to help users control where their online information is being sent.

"You will be able to tune the filtered [advertising] services by the number of sites that use them," Quirk said.

The IE9 RC is also adding ActiveX filtering, which aims to allow people to block ActiveX controls like Flash from running on web pages. Sites can be individually whitelisted, so users can let Flash video run on YouTube while blocking Flash-based advertising on the rest of the web.

Microsoft said it has improved IE9's performance since the beta release in September. Its Chakra JavaScript engine is now 35 percent faster and has better performance than Chrome's V8 on the Sunspider benchmark, according to the software maker.

"Microsoft's aim is not the benchmark, just that sites are faster for end-users," Quirk said.

To improve performance, the browser now features better ways of handling accelerated graphics, with the ability to automatically disable this feature if it will affect user experience, Microsoft said.

HTML 5 support

HTML developers will see improvements in the RC over the beta, with support for CSS 2D transformations and the ability to use WebM for video, if the codec is available.

There is added support for HTML 5's semantic tags, letting designers use descriptive HTML tags

The use of semantic tags should improve search engine indexes as well as helping define page layouts. Another change is that IE9 will now support HTML 5's geolocation features, using the World Wide Web Consortium's location specification.

Tom Hopkins, a managing consultant in EMC's Conchango consulting arm, is expecting IE9's HTML 5 features to be popular in enterprise web development.

"Projects that are starting now are asking for a rich interface, and HTML 5 for a development organisation is a tool for doing things in a supportable way," Hopkins said.

Developers wanting to work with just the latest HTML 5 features will be able to download a new version of the IE9 Platform Preview separately from the RC.

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