400 - Bad Requests when trying to install self-published app

[Glen Reesor]

Hi,
I'm working on a self-published app. It installs fine using Linux Firefox 41.0.2, however
when trying to install using Android Firefox 41.0.2, I get the error
"The page at http://192.168.0.101 says: 400 - Bad Request"

My manifest.webapp is located at 192.168.0.101/m3/, is served with the correct mime type
(application/x-web-app-manifest+json) and is shown below:
{
  "name": "m3",
  "package_path" : "http://192.168.0.101/m3/m3.zip",
  "description": "Cross platform mind mapping application",
  "launch_path": "/m3/index.html",
  "icons": {
    "128": "/m3/img/m3-128.png",
    "512": "/m3/img/m3-512.png"
  },
  "developer": {
    "name": "Glen Reesor",
    "url": "http://glenreesor.ca"
  }
}

This same manifest is also present in the root of the zip file.

The code I'm using to install it is:

function firefoxInstall() {
   var manifestUrl = 'http://192.168.0.101/m3/manifest.webapp';
   var requestInstall;

   requestInstall = navigator.mozApps.installPackage(manifestUrl);
   requestInstall.onsuccess = function() {
      alert(this.result.origin);
   };

   requestInstall.onerror = function() {
      alert(this.error.name);
   };
} // firefoxInstall()

The only thing I've been able to find is that, when trying to install from
the Android device, there is network traffic to ec2-52-27-229-12.us-west-2.compute.amazonaws.com.
This doesn't happen when trying install from the desktop.

Any thoughts on how to debug this further would be appreciated!

Glen