Good article. Another VAPID key generator site is helpful, too bad it doesn't seem to work. And even when you have what seems like a valid key, browsers might give errors of the form "Invalid VAPID token" which are very frustrating... And sometimes only happen in Firefox vs Chrome. Would like to see anyone do a more thorough write-up of this part though:<p>> In order to send web push notifications from your backend application server, you have to construct, encode, and encrypt the messages properly.<p>Basically, that's the hardest part, if you don't have library support of someone having done it for you already.<p>Web Push is both simple in design and yet frustrating. I gained some sympathy for sites that have opted not to support it after trying to do it myself without a library on a test page. (I'd only do it for real if anyone besides myself would use it, and just use the library.)