The addon itself does not advertise for Mr. Robot, Mr. Robot advertises for this addon.
https://research.mozilla.org/mixed-reality/
I'd charitably call it "Augmented Memory", but it's definitely not "Augmented Reality".
And I'd hardly call it a game, just a parasitic advertising gimmick that slows and bloats the browser. It just injects a bunch of JavaScript code, DOM elements and CSS effects into every tab.
There's really no game there, and it's pretentious to call it an "Alternate Reality Game", which is defined as "intense player involvement with a story that takes place in real time and evolves according to players' responses":
https://en.wikipedia.org/wiki/Alternate_reality_game
This extension just wraps all occurrences of a set of keywords (now including "fuck") in a span with some css animations and a tooltip that links to their web page.
https://github.com/gregglind/addon-wr/commit/da464ac8f1c3b08...
But in terms of memory usage, CPU and battery consumption, it's not that small, either.
It injects a blob of CSS and some JavaScript into every tab, then it does a regular expression search of every text node on each page, filtering out everything but paragraphs, then for each occurrence of a keyword in the text, it creates a new text node to split the current text node, then inserts a new span element between them, containing its own text node, then it creates an additional tooltip element containing six text nodes, five br elements, and one anchor element linking to https://support.mozilla.org/kb/lookingglass , and it also configures css class names to associate all those new nodes it created with the blob of css styling and animations that it injected.
This extension isn't the best example of their technology for Mozilla to be promoting and distributing, if they're really serious about delivering a fast memory efficient browser.