Examine source code of Mpurse

{
  "name": "Mpurse",
  "manifest_version": 2,
  "description": "Extension for Monaparty",
  "version": "0.5.2",
  "icons": {
    "16": "assets/mpurse16.png",
    "48": "assets/mpurse48.png",
    "128": "assets/mpurse128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://*/*"
      ],
      "js": [
        "extension_scripts/contentscript.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    }
  ],
  "background": {
    "scripts": [
      "extension_scripts/background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Mpurse",
    "default_icon": {
      "19": "assets/mpurse19.png"
    },
    "default_popup": "index.html"
  },
  "permissions": [
    "storage",
    "activeTab"
  ]
}