Embarrassingly, I need to remove WebGL from Browsh's features, as WebGL doesn't work in Firefox's headless mode. I certainly saw it working in the early days when I wasn't using Firefox headless in order to debug the injected CSS Browsh uses to render pages.
Sigh, so I best remove 'WebGL' from the homepage :(
Sigh, so I best remove 'WebGL' from the homepage :(