Your website is hosted on Cloud Storage, but it runs on your browser. If you use a self signed certificate on your backend, the browser can raise a warning because it doesn't trust this certificate.
So, you need to add the public key to your browser, not to your hosting system. or use a let's encrypt certificate, it's free and easy!
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…