I just posted a version with yield replaced by sleep. See if this fixes your key board issue.
Yes! Much, much better. Thank you.
I like the use of fractals to create different enemy types. But, I noticed my ship can pass safely through enemy ships; there is no collision detection. Also, the size of the enemies doesn’t seem to matter. I still have to target their cores, which always seem to be the same size. Hence, the look and size of the enemies don’t contribute to game play. I like the gradient lighting effect done on the walls. The player can’t pass through the walls, but bullets and enemies can which is really strange. The wall should be a fatal boundary, but it’s not. Gaining power-ups and new weapons is definitely a pro, but I don’t like losing weapons so easily. I like that you added bosses. What’s the point of the player being able to switch forms? Don’t I just want to be as small as possible? But, does my size matter anyway since they have to aim for my core? The game seems kind of repetitive. I got up to level 5 before giving up.