Examine source code of MobiDevTools

{
  "manifest_version": 2,
  "name": "MobiDevTools",
  "version": "3.7",
  "description": "DevTools-grade mobile developer console — free & open",
  "author": "Francesco De Stefano",
  "default_locale": "en",
  "permissions": [
    "tabs",
    "webRequest",
    "webNavigation",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png"
    },
    "default_title": "MobiDevTools"
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "@mobidevtools",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "content_security_policy": "script-src 'self'; object-src 'self'; style-src 'self' 'unsafe-inline'; font-src 'self' data:; img-src 'self' data: blob:; default-src 'self' data: blob:;"
}