On Tuesday, Facebook proudly boasted that it had found a way to defeat ad-blocking technology.
But this afternoon, a mere 48 hours since Facebook's boasts, Adblock Plus has unveiled a workaround that allows users to resume blocking ads on the social networking service.
"We promised that the open source community would have a solution very soon, and, frankly, they’ve beaten even our own expectations," Adblock Plus's Ben Williams writes today in a blog post.
He adds that the company is "still in a cat-and-mouse game" with the social networking service.
"Facebook might 're-circumvent' at any time," he writes. "This sort of back-and-forth battle between the open source ad-blocking community and circumventers has been going on since ad blocking was invented; so it’s very possible that Facebook will write some code that will render the filter useless -- at any time. If that happens, the ad-blocking community will likely find another workaround, then Facebook might circumvent again, etc."
This isn't the first time that one company has circumvented another's code, and probably won't be the last. Consider, Apple's Safari browser has long blocked tracking cookies by default. But that didn't stop Google (and others) from figuring out how to circumvent the no-tracking settings in order to serve targeted ads to Safari users.
For its part, Facebook said the new Adblock Plus code also blocks some content, including posts from friends.
"We're disappointed that ad blocking companies are punishing people on Facebook," the spokesman stated. "This isn't a good experience for people and we plan to address the issue."
The response rings somewhat hollow, considering that Facebook started this war with AdBlock Plus by circumventing it -- and obviously frustrating some users -- in the first place. Facebook may argue that its business plan requires it to show ads, but people who have gone out of their way to install ad-blockers presumably feel their experience is diminished by those ads.