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Sleipnir review


Sleipnir’s star attraction is its ability to switch between Internet Explorer and Firefox’s rendering engines, but it’s no racehorse

Review Date: 12 Mar 2010

Reviewed By: Hani Megerisi

Price when reviewed: Free

Overall Rating
5 stars out of 6

Features & Design
5 stars out of 6

Ease of Use
5 stars out of 6

There’s something exciting about the prospect of using a browser named after an eight-legged horse, with Sleipner – as all good mythology followers will know – the steed of Odin in Old Norse legend. And in many ways, it doesn’t disappoint.

Uniquely among all 12 browsers offered by the EU browser ballot screen, Sleipner gives you the option of choosing the Gecko (as used by Mozilla) or Trident (as used by Internet Explorer) rendering engine. By default it uses Trident, but if you download the ActiveGeckoBrowser plugin then Mozilla’s browser engine appears in Sleipner’s options box.

As you'd expect from a browser that declares itself

Sleipnir’s customisability doesn’t stop there. Quite aside from the downloadable skins, a “design” feature lets you choose one of three layouts. There’s one for fans of Internet Explorer 6, another called “Simple” (the default choice) and a third which mimics an older Sleipner layout. We recommend Simple.

There aren’t many plugins – just 13 – and they’re of varying use. Glanchip provides a preview of a tabbed window when you hover the tab, while the Superdrag extension allows mouse gestures. SnapCrab, described as “a useful plug-in for taking a screenshot of the web page”, may seem a useless addition, but it does give you the option of capturing the mouse cursor along with the page (useful for training purposes).

The OpenLink Extension is less impressive. It gives you “more options” when downloading and opening files, but the extra options are changing the download location and offering you the choice to open from the web – features available as standard in the bigger browsers.

Sleipnir is native to Japan, where it enjoys huge success as the third most popular web browser (behind Internet Explorer and Firefox) with double the market share of Chrome. Compared to the Chinese browsers such as GreenBrowser this doesn’t affect the user interface, which follows a similar logic to Mozilla Firefox, but Sleipnir’s Japanese origins become very obvious in the support page. Half is in Japanese and the other half is translated with only mixed success.

Another issue is speed. Under Windows XP, and using Internet Explorer 7’s rendering engine, we found Sleipnir infuriatingly clunky and slow. Load up more than three or four tabs and the system slowed down even further, and at seven tabs, it gave up and crashed.

On switching to Windows 7 and Internet Explorer 8’s engine, however, we had no problems with stability. It still wasn’t the quickest in our tests: 6,395ms in SunSpider is mid-table at best, while a 3.8secs startup time is nothing to boast about.

There’s still a lot to like about Sleipnir. While it doesn’t live up to its speed claims, the ability to instantly switch between Gecko and Trident rendering engines is geekily fantastic – you can even switch by clicking on the icon at the bottom-left of the window. Unlike most of the other browsers we’ve looked at outside the major five, this is one browser we won’t be uninstalling.

Author: Hani Megerisi

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User comments

If you like the rendering engine feature so much....

you should absolutely check out IETab, which does the same thing right there in your favourite Firefox:

By storm311 on 15 Mar 2010

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