Examine source code of PnaPna CRM

{
  "manifest_version": 2,
  "name": "PnaPna CRM",
  "version": "0.1",
  "description": "PnaPna is a powerful CRM Project Management Tool",
  "icons": {
    "48": "assets/icon_48.png",
    "96": "assets/icon_96.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "accutechhi@gmail.com",
      "strict_min_version": "42.0"
    }
  },
  "background": {
    "scripts": [
      "assets/jquery.min.js",
      "assets/popup.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "19": "assets/icon_19.png",
      "38": "assets/icon_38.png"
    },
    "default_title": "PnaPna Firefox Extension",
    "default_popup": "pnapna.html"
  },
  "commands": {
    "toggle-feature": {
      "suggested_key": {
        "default": "Ctrl+Shift+Y",
        "linux": "Ctrl+Shift+U"
      },
      "description": "Opens popup.html"
    }
  },
  "content_security_policy": "script-src 'self' https://pnapna.com; object-src 'self'",
  "content_scripts": [
    {
      "exclude_matches": [
        "*://developer.mozilla.org/*"
      ],
      "matches": [
        "*://*.mozilla.org/*"
      ],
      "css": [
        "assets/style.css"
      ],
      "js": [
        "assets/jquery.min.js",
        "assets/popup.js"
      ]
    }
  ],
  "default_locale": "en",
  "page_action": {
    "default_icon": {
      "19": "assets/icon_19.png",
      "38": "assets/icon_38.png"
    },
    "default_title": "PnaPna Firefox Extension",
    "default_popup": "pnapna.html"
  },
  "permissions": [
    "webNavigation"
  ],
  "user_scripts": {
    "api_script": "apiscript.js"
  },
  "web_accessible_resources": [
    "assets/icon_128.png"
  ]
}