Examine source code of WebGraph

{
  "manifest_version": 2,
  "name": "WebGraph",
  "version": "1.0.0",
  "description": "Visualize your browsing as an interactive node graph",
  "permissions": [
    "tabs",
    "storage",
    "activeTab",
    "webNavigation",
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "webgraph@philxd",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "browser_action": {
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png"
    },
    "default_title": "Open WebGraph"
  },
  "background": {
    "scripts": [
      "message_types.js",
      "background.js"
    ],
    "persistent": true
  },
  "content_scripts": [],
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "96": "icons/icon96.png"
  },
  "web_accessible_resources": [
    "graph/index.html"
  ]
}