Many Firefox Quantum users were taken by surprise yesterday when they found a strange new plugin listed in their browsers. The plugin was called Looking Glass and even though it was disabled by default, users weren’t pleased to see a plugin they knew nothing about pop up out of nowhere. While Mozilla has since offered an explanation, it has understandably taken a lot of flak from users for sneaking in a Firefox plugin.

The description of the Looking Glass plugin didn’t do much to address users’ concerns, it just said “MY REALITY IS JUST DIFFERENT THAN YOURS.”

Users took to the official support forum to inquire more about the mysterious plugin. Some couldn’t find any references to it online which only added to their suspicions.

The plugin was actually part of Mr Robot’s alternative reality game. It’s a trail of clues that the writers have left for the fans to discover. The plugin was developed as a “shared experience to further your immersion into the Mr Robot universe,” says Mozilla.

Once the plugin was enabled, it made minor changes to select websites which provided players of the game with more clues. It may have been developed with good intentions but many Firefox users criticized Mozilla for distributing a plugin without their permission.

The company has since moved the plugin to Firefox’s public add-on store and has also made its code available in a public repository. It also said in a statement that the plugin “never collected any data, and had to be explicitly enabled by users playing the game before it would affect any web content.”

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