Opera Software will launch a new, streamlined user interface in Opera 11.5,  that mirrors the minimalist design of its competitors.

The new interface, dubbed "Featherweight" by Opera, features only four buttons alongside the address bar, and loses much of the "chrome" -- a browser's interface elements, not Google's application -- to expand the amount of display space for websites.

Featherweight will be the default user interface (UI) for Opera starting with version 11.5, which appears to be close to shipping.

It also closely resembles the UI direction first taken by Google and its Chrome, which Microsoft and Mozilla both followed with their Internet Explorer 9 (IE9) and Firefox 4 that launched earlier this year.

According to Jan Standal, Opera's vice president of desktop software, Featherweight was its reaction to complaints by users that Opera felt slow.

"Even though Opera is extremely fast -- fast at opening and closing tabs, opening windows -- we got reports from users that they felt Opera was slower than other browsers," said Standal. "We wanted to make the browser feel lighter and faster, but keep its functionality."

Standal also echoed arguments made by others, most notably Microsoft, that ditching extra chrome allows more of the Web page itself to show.

When Microsoft first revealed IE9's interface last September, it touted the muting of the browser . "People go to the Web for sites, not for the browser," said Dean Hachamovitch, vice president for IE, at IE9's beta release event last year.

Standal said much the same today. "We wanted to leave as much room for the Web page as possible," said Standal, "and move to a more application-style window."

But he denied that Opera was simply copying the work of others. "Count the amount of pixels," he argued. "We were already there with a light interface. People just didn't see it that way."

Even so, Standal acknowledged that Opera has been working on the Featherweight UI for just six months, a timeline that preceded the release of IE9 and Firefox 4, but followed Microsoft's and Mozilla's showing their browsers' new designs.

Opera has issued a string of "release candidate" (RC) builds of Opera 11.5 in recent days, which hints that a final version will ship shortly.

 Opera 11.5 RC5  can be downloaded from the company's website for Windows, Mac OS X and Linux.

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