Examine source code of enhance PDF experience

{
  "manifest_version": 2,
  "name": "__MSG_extName__",
  "short_name": "__MSG_extName__",
  "version": "1.5.27.9",
  "description": "__MSG_description__",
  "default_locale": "en",
  "homepage_url": "https://abcdpdf.com",
  "author": "abcdpdf.com",
  "browser_action": {
    "default_icon": "images/icon/icon48.png",
    "default_title": "__MSG_extName__",
    "default_popup": "/popup/index.html"
  },
  "chrome_url_overrides": {
    "newtab": "/dist/index.html"
  },
  "icons": {
    "16": "images/icon/icon16.png",
    "32": "images/icon/icon32.png",
    "48": "images/icon/icon48.png",
    "128": "images/icon/icon128.png"
  },
  "background": {
    "scripts": [
      "js/misc.js",
      "js/background.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "js": [
        "js/content_script.js"
      ],
      "matches": [
        "<all_urls>"
      ],
      "run_at": "document_start"
    }
  ],
  "offline_enabled": true,
  "permissions": [
    "bookmarks",
    "history",
    "contextMenus",
    "tabs",
    "https://*.abcdpdf.com/",
    "https://www.yahoo.com/"
  ],
  "browser_specific_settings": {
    "gecko": {
      "strict_min_version": "58.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "id": "{a9fb4445-6586-485f-b752-00b69c42d433}"
    }
  }
}