The Electronic Frontier Foundation (EFF) has released a beta version of Privacy Badger, a browser extension for Firefox and Chrome that detects and blocks online advertising and other embedded content that tracks you without your permission.

Privacy Badger was launched in an alpha version less than three months ago, and already more than 150,000 users have installed the extension. Today's beta release includes a feature that automatically limits the tracking function of social media widgets, like the Facebook "Like" button, replacing them with a stand-in version that allows you to "like" something but prevents the social media tool from tracking your reading habits.

"Widgets that say 'Like this page on Facebook' or 'Tweet this' often allow those companies to see what webpages you are visiting, even if you never click the widget's button," said EFF Technology Projects Director Peter Eckersley. "The Privacy Badger alpha would detect that, and block those widgets outright. But now Privacy Badger's beta version has gotten smarter: it can block the tracking while still giving you the option to see and click on those buttons if you so choose."

EFF created Privacy Badger to fight intrusive and objectionable practices in the online advertising industry. Merely visiting a website with certain kinds of embedded images, scripts, or advertising can open the door to a third-party tracker, which can then collect a record of the page you are visiting and merge that with a database of what you did beforehand and afterward. If Privacy Badger spots a tracker following you without your permission, it will either block all content from that tracker or screen out the tracking cookies.

Privacy Badger is one way that Internet users can fight the decision that many companies have made to ignore Do Not Track requests, the universal Web tracking opt-out you can enable in your browser. Privacy Badger enforces users' preferences whether these companies respect your Do Not Track choice or not. Advertisers and other third-party domains that are blocked in Privacy Badger can unblock themselves by making a formal commitment to respect their users' Do Not Track requests.

"Users who install Privacy Badger aren't just getting more privacy and a better browsing experience for themselves—they are providing incentives for improved privacy practices and respect for Do Not Track choices across the Internet," said Eckersely. "Using Privacy Badger helps to make the Web as a whole better for everyone."