Examine source code of Meta4 ClickOnce Launcher

{
  "applications": {
    "gecko": {
      "id": "m4clickonce@meta4.com"
    }
  },
  "manifest_version": 2,
  "name": "Meta4 ClickOnce Launcher",
  "description": "This extension enables ClickOnce apps in Firefox.",
  "icons": {
    "16": "icons/earth-download-16.png",
    "32": "icons/earth-download-32.png",
    "48": "icons/earth-download-48.png",
    "64": "icons/earth-download-64.png",
    "128": "icons/earth-download-128.png"
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "nativeMessaging",
    "http://*/*",
    "https://*/*"
  ],
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "web_accessible_resources": [
    "nativeinstall.html",
    "js/nativeinstall.js",
    "images/download.png",
    "images/download_warning.png",
    "images/exec_dialog.png",
    "m4clickoncehelper.dat"
  ],
  "version": "1.3.1"
}