title: didReceiveRemoteNotification not called in iOS 13.3 when app is in background
body: <p>I am banging my head. I am implementing push notification. Everything is working fine (push is received, badge is updated) but under iOS 13.3 the method application(_:didReceiveRemoteNotification:fetchCompletionHandler:) is not called when the app is in the background. If the app is in the foreground or using an iOS 12 device the method is called. I register for push notification in the following way: </p>
  
  <pre><code>[[UNUserNotificationCenter currentNotificationCenter] requestAuthorizationWithOptions:(UNAuthorizationOptionBadge | UNAuthorizationOptionSound | UNAuthorizationOptionAlert) completionHandler:^(BOOL granted, NSError * _Nullable error) {
      if (granted) {
          dispatch_async(dispatch_get_main_queue(), ^{
              [[UIApplication sharedApplication] registerForRemoteNotifications];
          });
      }
  }];
  </code></pre>
  
  <p>The payload is set to the following</p>
  
  <pre><code>{"aps": {
      "badge": 10,
      "alert": "test",
      "content-available": 1
  }}
  </code></pre>
  
  <p>I tried adding "Remote notifications" and "Background processing" as app capabilities in all variations (only "Remote notifications"/"Background processing", without any of those capabilities, enabling both) without any change. I set the delegate for the UNUserNotificationCenter but again without success. I set the headers accordingly:</p>
  
  <pre><code>curl -v \
   -H 'apns-priority: 4' \
   -H 'apns-topic: xx.xxxxx.xxxx' \
   -H 'apns-push-type: alert' \
   -H 'Content-Type: application/json; charset=utf-8' \
   -d '{"aps": {"badge": 10,"alert": "test", "content-available":1}}' \
   --http2 \
   --cert pushcert.pem \
   https://api.sandbox.push.apple.com/3/device/1234567890
  </code></pre>
  
  <p>From the docs it states that this method is called even when the app is in background:</p>
  
  <blockquote>
    <p>Use this method to process incoming remote notifications for your app.
    Unlike the application:didReceiveRemoteNotification: method, which is
    called only when your app is running in the foreground, the system
    calls this method when your app is running in the foreground or
    background.</p>
  </blockquote>
  
  <p>What am I missing here for iOS 13?</p>