title: CSS image mask broken in Cordova for iOS 11.x?
body: <p>I use -webkit-mask-image in my meteor app, like this:</p>
  
  <pre><code>...
  background-color: purple; 
  -webkit-mask-image: url('images/user_plum.png');
  ...
  </code></pre>
  
  <p>It works fine in all browsers. It works fine in the cordova version on Android. It <em>was</em> working fine in iOS Cordova. Now, only in iOS, all of my icons that use this technique are invisible, even though they are still clickable and functioning.</p>
  
  <p>The problem was found on two users' iPhones and I reproduced it in iOS Simulator. My iPhone worked fine. Uninstall/reinstall of the app, rebuild/restart of the server, etc., nothing changed. Until I updated my phone to iOS 11.4, and now my phone has the issue, too. If I remove that -webkit-mask-image line from the CSS, I universally get the proper background-color'ed square where the icon should be. That and other simulator testing makes it clear the invisible icons are only happening on iOS devices and simulator, and only if -webkit-mask-image is in use. Is anyone aware of any changes in iOS between 11.1 and 11.4 that would break Cordova webview's handling of -webkit-mask-image?</p>