SAPUI5 hybrid app - Add custom icon to push notification

Question

Is it possible to add a custom icon to push notification when using kapsel-plugin-push?

I have read blogs, like:

• Getting Started With Kapsel - Part 4 - Push
• How to config and consume Push Notification from SAP Mobile Services

and tried to add icon property to gcmNotification. Icon appeared in notification, but after that, there was no sound when notification arrives (I have fixed that issue by adding sound property). Also notification payload is not applicable (data in notification was not processed by application).

If I remove gcmNotification, notification sound is working as well as data in notification payload.

---

I am sending requests to SCPms via Postman. Here is an example of

{
  "alert": "Test alert",
  "data": "{\"TSLASTTEMP\":\"Sat Mar 31 2018 18:09:02\",\"LASTTEMP\":\"35\", \"NUMBER\": \"1231244234/2a\"}",
  "sound": "default",
  "gcmNotification": {
    "icon": "sap",
    "color": "blue"
  }
}