The browser blockers: Is browser sniffing outdated

"We've been reaching out to Webmasters, and they've been fixing those," says Brian Rakowski, Google's director of product management for Chrome.

Bruce Lawson, Web evangelist at Opera, says, "It's a core issue in that it has to do with Web developers coding for a browser" -- in other words, making use of a given browser's proprietary features rather than using standards, which he calls "not a very sustainable development strategy."

Lawson explains: "Some banks do browser-sniffing where they attempt to discover which browser you're using, and if it's not IE they bounce you away. This is folly, since it's easy to set your browser to pretend to be IE, in which case it'll let you in and, more often than not, everything works fine -- so there was no point in rejecting non-IE browsers in the first place. It's also folly, since you might lose customers; most mobile phone users are using Opera or Safari on an iPhone rather than IE, for example, and that's a hugely growing market."

Fortunately, this happens less and less, Lawson says.

For those sites that do still practice this, many of them check what's called the "user agent string" in the browser against a whitelist of approved browsers -- or a blacklist of rejected ones. But by the user, or by browser add-ons the user has installed. Even strings in new browsers have contained keywords that have confused browser detection schemes, says , director of development at .