Hacker News Reader

Thanks for pointing it out, I'll look into it.

Me too. Jumping into the console gives a series errors like:

> TypeError: tetrisBoard[(y - 1)] is undefined

From within tick()

Seems to be triggered by rotation followed by a drop.

Seconding that, Firefox 49 on Windows7.

Thirded w/ Chrome 54.0.2840.87 (64-bit) on OS X 10.11.6. Stopped about 15 pieces in the first time so I thought it was just an abbreviated demo.