Of course! I was using chrome on a MacBook when I got the bug. I tried later on chrome on a windows PC and the bug didn't happen! It didn't happen playing the downloaded windows build either.
Thanks for getting back to me! The other commenter said he was using Chrome on a Mac too - that's so bizarre, I didn't think OS would have much of an impact on a 2D web browser game! I'll add a note to my jam page. Hope you enjoyed the actual game!