New feature lets Firefox users obtain search results more quickly, but some worry they'll be sent content they don't want.
Reza Behforooz, a software engineer at Google, announced on Wednesday that the search engine now preloads the top search result into the cache of Mozilla browsers.
"Now Google's faster than ever on Firefox and Mozilla browsers," Behforooz said in a posting on the company's blog. "When you do a search on these browsers, we instruct them to download your top search result in advance, so if you click on it, you'll get to that page even more quickly."
The search engine's preloaded link feature is supported by Mozilla browsers, including Firefox, but because Microsoft's Internet Explorer and other browsers do not provide such functionality, they will not be able to use the feature.
There are some potential issues, however. Google points out in an FAQ that "you may end up with cookies and Web pages in your Web browser's cache from Web sites that you did not click on."
A few Firefox users have expressed concern about this feature on the Mozillazine site. They say people risk unknowingly downloading illegal content, and could end up using more bandwidth when surfing.
"You'll run into trouble if the first match is a porno site and your company's proxy logs it--you get all cookies of the first match without seeing the page," one Firefox user said.
Another user, Alex Bishop, said that even if people unknowingly download illegal content using the link feature, the content is flagged in a different way from content they've chosen to download.
"An 'x-moz: prefetch' header is sent with the request, and the referrer header will match the Google search results page," Bishop said.
Ingrid Marson of ZDNet UK reported from London.