content won't show for me (latest firefox beta, 56b05) : Failed to register/update a ServiceWorker for scope ‘https://stenciljs.com/docs/’: Bad Content-Type

content won't show for me (latest firefox beta, 56b05) : Failed to register/update a ServiceWorker for scope ‘https://stenciljs.com/docs/’: Bad Content-Type of ‘text/html’ received for script ‘https://stenciljs.com/docs/sw.js’. Must be ‘text/javascript’, ‘application/x-javascript’, or ‘application/javascript’. Error DOMException [SecurityError: "The operation is insecure." code: 18 nsresult: 0x80530012] intro:19:41