Earlier this week, an anti-Semitic browser extension called “Coincidence Detector” hit the Chrome add-on library, and now following public outrage, Google has pulled the extension citing its hate speech policy.

The extension worked by building a database of Jewish people and bracketing their names  with parentheses wherever they appeared on the web. For example, John Doe would become (((John Doe))). This symbol, called an “echo,” has apparently been in use by a number of anti-Semitic groups online to expose and target Jewish people.

The purpose of Coincidence Detector, according to the extension’s creators, was to point out an alleged conspiracy of Jewish people in the media and the supposed Jewish agenda that they are pushing. Of course, this extension could also be used to target Jewish people for online harassment, and according to a report by Mic, a number of users began sending threatening messages to people like Jonathan Weisman, a deputy editor for the New York Times.

“The anti-Semitic hate, much of it from self-identified Donald J. Trump supporters, hasn’t stopped since,” Weisman wrote in an article detailing the harassment.

According to Engadget, the extension had just under 2,500 users before it was pulled, and it had already built a database of nearly 9,000 names.

It is surprising that something like Coincidence Detector could even make it onto the Chrome Web Store in the first place, but Google does not appear to screen extensions before they are added to the site. Instead, they review potentially harmful add-ons only if they have been reported by users.

The developer policy specifically cited by Google in its removal of Coincidence Detector states that “We don’t allow content advocating against groups of people based on their race or ethnic origin, religion, disability, gender, age, veteran status, or sexual orientation/gender identity.”

Screenshot via Chrome Web Store