Information Gift

Mozilla 1.2 Released

Mozilla 1.2 was released yesterday (Mac|OS X|Win) . This release is mostly an interface tune-up, at least as far as the browser component is concerned, adding Type Ahead Find for link and page text, native form widgets in WinXP, and "image selection visualization" (now you get an annoying rectangle appearing around your images and your text links while tabbing through a page; usable, yes, pretty, no). Java now works again on Mac OS X.2.x, though gifs with transparent backgrounds still print as black on Mac and Linux platforms.

There is one new feature that might interest web developers...

From the Link prefetching FAQ:

"Link prefetching is a browser mechanism, which utilizes browser idle time to download or prefetch documents that the user might visit in the near future. A web page provides a set of prefetching hints to the browser, and after the browser is finished loading the page, it begins silently prefetching specified documents and stores them in its cache. When the user visits one of the prefetched documents, it can be served up quickly out of the browser's cache."

Looks like the Mozilla team has thought this through and covered all their bases. They've delivered a smart mechanism that's easy to implement and shouldn't unduly tax servers or bandwidth, as prefetching only occurs when the browser is doing nothing else and you, the developer, decide what to prefetch.

The most common prefetching "hint" is likely to be in the form of the HTML <link> tag:

<link rel="prefetch" href="/images/big.jpeg">

The FAQ goes on to list <meta> and HTTP Link: header alternatives and give background on how the browser handles prefetching requests and user interaction.

Caveats:

For reasons of security and performance, SSL sites and sites using <link> tags with query strings are not prefetched.

Until prefetching is standardized (an Internet-draft is in the works) and feature support is picked up by, oh, um, Microsoft, your work in this area will have little impact for general audiences.

Developers have used Javascript hacks in the past to prefetch content, but a browser feature-based approach is cleaner and should offer a better and easier to implement experience for the end-user.

Posted by Lewis Francis at November 28, 2002 11:04 PM