OK, the problem seems to be a third party shader I'm using. Thing is, I've been using it for a while now and it used to be OK. Now it fails to initialize, an In Promise error. This, btw, only happens with Worker running:
Uncaught (in promise) Error: failed to find shader program 'bright_gray_fog'
Any clue what has changed recently(ish) that could affect this?
THanks