The popular open-source browser already contains a pop-up blocker by default, but this does not handle pop-ups launched by plug-ins such as Flash and Java. Mozilla employee Asa Dotzler wrote in his blog last week that Mozilla developers are responding to the increasing number of advertisers that are using plug-ins to launch pop-up ads.
"A lot of people have been reporting a new breed of pop-ups on the Web," Dotzler said. "This increasing menace is rooted in the pop-up capabilities of plug-ins like Flash and Java. If you're seeing pop-ups and pop-unders, you're probably visiting sites that have Flash or other plug-ins and those plug-ins are being exploited by advertisers to abuse you with annoying pop-ups and pop-unders."
Firefox 1.0 can block pop-ups launched by plug-ins, but this feature is disabled in the default set-up because it would affect Web sites that rely on plug-in triggered pop-ups for legitimate functionality, according to Dotzler. The beta patch resolves this issue by enabling users to whitelist sites where pop-ups are needed.
The beta patch has been packaged as a Firefox extension, called PopupsDie, and can be downloaded for testing here.
Ingrid Marson of ZDNet UK reported from London.