I really enjoied that game! But the fullscreen didnt work, and for me as someone who doesnt live in the USA the captcha was just guessing and dit cost a lot of time.
2 years ago (+1)
Its 2560x1600. (I tried to change the resolution but it was the same) It stays as big as it would be without fullscreen and just ads a black frame:
I then tried an other device (2736x1824) but it was the same. If I zoomed in with my browser the image got bigger. I tried Firefox and Edge.