The mysterious plugin was installed without explanation, just with the ominous phrase "My Reality is Different Than Yours", sparking fears that it was some kind of malware.
It later came to light that the plug-in was simply an ad, part of a promotion for the USA Network hacker show Mr. Robot.
The extension was installed on users' devices without prior permission and uploaded text, images and game clues to websites. The only permission it was for was to a program called Shield Studies, which enabled Firefox's creators to gather data for improving the browser in the future.
As you can probably imagine, Firefox users quickly took to Reddit and the like, as well as Firefox's support forum to vent their concerns or go mental about privacy concerns.
One user wrote on Mozilla's Firefox support forum: "I did not remember installing this add-on, I would not knowingly install it. Firefox, Antivirus and OS are all up-to-date. Any explanations welcome [sic] because I can't find any reference online."
According to The Verge, Mozilla responded quickly, moving the game extension to the Firefox add-on store and making its code public.
"While the web extension/add-on that
was sent out to Firefox users never collected any data, and had to be
explicitly enabled by users playing the game before it would affect any
web content, we heard from some of our users that the experience we
created caused confusion," Mozilla said, although didn't promise to
never do it again. We are watching you, Mozilla! µ
