I restarted my computer and it works. Kind of fun. I did run into a separate bug on Win10, Chrome/WebGL - The game took mouse focus. I hit alt tab to do something else on my computer, and after clicking back into it, it shot instantly, would not move any more with the mouse, and clicks just kept firing at the same spot.
Yup yup, that one we know about. The WebGL version was packaged after we had already submitted it to the game jam, so the mouse capture logic never got adapted. If I get some free time I may look into it, mainly just for my own edification on how that process differs in WebGL :)
Thanks for playing though!