Fun :) Thank you for the comment.
Unfortunate about that PC issue; I don't believe Javascript code sandboxed in a browser could cause such a thing, but perhaps there was a bug with the browser or something else with your PC's hardware. I've never had this issue you mention and haven't seen anyone else comment about it.
I've been hard at work on a desktop game Journey to Royn for 12 months. A newer version of Idle Tetris exists on my computer (with fun things like unique and wacky achievements with rewards), but I'm not likely to work on it for a bit because of my large complex exciting project.