For some reason, I couldn't get it to run when installing from the 'play' link. I had to download the zip and run it from there. Probably a Byond issue, but figured I'd mention it here as well.
I got the ball 'stuck' at one point.
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It stuck to the edge of my paddle when I caught it right up against the wall, and I couldn't get it off.
Well done overall, though the moving background annoys me a little.
Yea I also had to download zip to play and run it from there