"bug": when you view the challenges menu in the browser without being full screened, the arrows that switch between the pages are partially hidden behind the challenge buttons.
Bug: dying after completing the game (you do this by facing downwards) puts you back in a semi-frozen main menu after the credits. You can enter the settings, but the background is frozen, and you can't start an adventure or enter the challenge menu. Tested on chrome.
Dunno where to post all these bugs, they clog up the comments.