build/lib/electron.ts/darwinBundleDocumentType
function darwinBundleDocumentType(extensions: string[], icon: string) {
	return {
		name: product.nameLong + ' document',
		role: 'Editor',
		ostypes: ['TEXT', 'utxt', 'TUTX', '****'],
		extensions: extensions,
		iconFile: icon
	};
}