Examine source code of Egghead History

{
  "name": "Egghead History",
  "version": "1.0.4",
  "description": "A delightful browser history extension",
  "icons": {
    "16": "icon-16.png",
    "48": "icon-48.png",
    "96": "icon-96.png",
    "128": "icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content-script.js"
      ]
    }
  ],
  "manifest_version": 2,
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "egghead-history@camfeenstra.com"
    }
  },
  "content_security_policy": "script-src 'self' 'wasm-unsafe-eval'; object-src 'self';",
  "permissions": [
    "storage",
    "webNavigation",
    "tabs",
    "alarms",
    "history",
    "scripting",
    "http://*/",
    "https://*/"
  ],
  "browser_action": {
    "default_popup": "popup.html"
  },
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Ctrl+Shift+Y"
      },
      "description": "Open popup"
    }
  }
}