Looks like it's a promo for Mr Robot, which is really not ok.
> What's happening? Are you a fan of Mr Robot? Are you trying to solve one of the many puzzles that the Mr Robot team has built? You’re on the right track. Firefox and Mr Robot have collaborated on a shared experience to further your immersion into the Mr Robot universe, also known as an Alternate Reality Game (ARG). The effects you’re seeing are a part of this shared experience.[0]
EDIT: looking at this[1] comment, perhaps it's not a promo?
[0]: https://support.mozilla.org/en-US/kb/lookingglass [1]: https://www.reddit.com/r/firefox/comments/7jh9rv/what_is_loo...
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