The game assets are repackaged into an iframe, allowing the game to load inside an entirely unrelated web page that firewalls view as safe.
Check which side of the road cars are on. This immediately eliminates large portions of the world (e.g., driving on the left is common in the UK, Australia, Japan, and South Africa). Language and Script: world guesser unblocked repack
You can find the World Guesser unblocked repack on various community-driven sites. The game assets are repackaged into an iframe,