While Dave Dash was representing Mozilla to participate in the Add-on-Con event, he was given a Google Chrome extension puzzle as a door-gift. And this puzzle is actually an enlarged QR code (a matrix code or two-dimensional bar code that most current Japanese mobile phones can read with their camera). After scanning it with a QR code scanner, it would lead you to a secret Google Chrome extension URL. Whoever finds it will win a prize.
In my own opinion, this puzzle seems “impossible to complete”. I’m indeed very curious how is it possible to piece together a puzzle that contains lots of blurry images. Dave said he and his wife took “a few days” to finish the puzzle. If it were to be me, I would have given up within an hour.