Sample 3D platformer not work in HTML5 (black screen)

Hi guys I’m new to Defold, using version 1.13.1

I downloaded the sample-3d-platformer from GitHub but building a regular desktop version was a real struggle so from start I kept getting 5 errors in the console. The only thing that fixed it was completely deleting the context section from game.appmanifest in the win32 parts (wtf? what a great start :smiling_face_with_tear: )
Okay, after that I tried building for the web but just get a black screen.
Does anyone know what might be causing this? Is it all down to the shadow shaders? If so, how do I get them to work on the web?