This is odd ... but it's not like Google doesn't do the same thing all the time, at least to a degree. Look at its most recent interactive Google Doodle, the M

This is odd ... but it's not like Google doesn't do the same thing all the time, at least to a degree. Look at its most recent interactive Google Doodle, the Moog keyboard. When you accessed the page on Firefox, there was a little note that said something like, "Consider upgrading to a modern browser like Chrome to get the full experience." (I think the Chrome version made use of a different method for producing the audio -- presumably implemented for the sole reason of promoting Chrome.)