Yes, it was made on MacOS. This is not the only project I had problems with a black screen. This has been happening to me since 2021.3.16f1 was released. I expected it to work since I could run it on MacOS which had a similar issue. I have new builds of the game. I'll talk to the person who runs the jam to see if it would be possible to update the game and upload a WebGL too just in case.
I didn't upload a WebGL version because the game was quite big and didn't think it would be possible to run it without issues.