Thanks for your feedback, I'm sorry about your browser! The "game saved" window is here because previously quitting would just lag your browser and leave you on a slowed-down title scene, so I added this because I couldn't figure out a way to detect browsers. You're definitely the first to report a crash though.
Regarding the music I couldn't find what kind of soundtrack would fit the game... and for the leaps reference, well, it's a platformer ;)