Better ad blocking starting with Firefox 2.0.0.4

Two patches have been added to Firefox code recently that will improve content blocking as soon as mid May, the estimated release date for Firefox 2.0.0.4.

The patches ensure that content requested by plugins like Flash and Ajax based applications will be subject to the same content policies as regular web pages. So if for example you have asked to block images from server “http://ads.server.net” they will be blocked even if requested by a Flash application or an XMLHttpRequest, one of the core functions used by rich Ajax-based web applications.

Yahoo! Maps, for example, embeds ads in its Flash-based application. These ads are not subject to regular content filtering and so, are displayed even if using an ad blocking extension like Adblock Plus.

Wladimir Palant, author of Adblock Plus, filed and developed the patches for these bugs. He also announced that version 0.7.5 of Adblock Plus, currently in release candidate status, will use the new capabilities to provide stronger ad blocking.

I could verify this using a Firefox 2.0.0.4 nightly and the Adblock Plus release candidate available at Palant’s web site.

This is definitely a welcome improvement. If not for something as trivial as ad blocking, which is what pays the bills in many cases, there are more important situations like parental controls and public libraries that will benefit from this as well.