JSONRPC.NotifyAll – Help to send Notification via URL

I want to show a popup notification in KODI.

Can anyone help me to build a json request via HTTP.
I want to send via HTTP command a simple Message.

I tried this, but I don’t get any feedback back:
http://192.168.1.87:8080/jsonrpc?request={“jsonrpc”: “2.0”, “method”: “JSONRPC.NotifyAll”, “params”: {“sender”: “homee”, “message”: “Test”}, “id”: 1}

If I try it I get no response back and no notifications inside Kodi.