I was controlling the spaceship, it was stage 3 or 4. And I think I hit the asteroid when that happened.
The spaceship part has three stages, so you were in the final stage of the spaceship. When dying in the final stage, you should automatically appear on the first tetris level (tetris minitutorial). I still don't understand what happened within the code... I tried to replicate your bug, but it worked well for me on different tries with different browsers (Firefox, Chrome & Edge).
Either way, thanks for the reply!