shit. It works in the editor (unity) but not in the build :-O I try to fix it somehow.
Viewing post in Social Distancing jam comments
OK, found the bug. Unity generates physics data in the editor by default for sprites, but not in the build. Now it works, thanks for reporting!
Oh nice. I cannot update the binaries because the voting is being done... So I uploaded the new binaries to here: https://drive.google.com/open?id=1nCIrhooEfRViBtvzR3PjqvlhJUltXmd5