about black screen in Chrome https://forum.defold.com/t/black-screen-in-browser/3990
about ferrofluid: there was a requirement that game should be new and created just for jam
my game with ferrofluid was started on Unity (have some code and simple prototype with simple sprites (no real ferrofluid)) - as I understand, if I port this prototype to Defold and continue to develop it, it will not take part in a Jam because of rules