With Celeste Ultimate Shining Wonder bouncing off of Abrams dummy and green physics ball in lobby, it is possible to have the ultimate's object bounce into the ball as it is entering the Sandbox teleporter, causing an immediate game crash. I had it crash my game first on accident from the random bouncing of the green ball object and could replicate it one more time before sending this. It is unlikely for this crash to occur, but may happen at random in the lobby while practicing with Celeste.
Setup looks roughly like this:
Setup looks roughly like this: