Examine source code of Furigana

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "version": "1.0.2",
  "description": "Add furigana",
  "icons": {
    "38": "icons/icon.svg"
  },
  "web_accessible_resources": [
    "dict/*.dat"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "dist/content.js"
      ]
    }
  ],
  "default_locale": "en",
  "browser_action": {
    "default_icon": {
      "38": "icons/icon.svg"
    },
    "default_title": "furigana",
    "default_popup": "setting/options.html"
  },
  "permissions": [
    "<all_urls>",
    "storage",
    "contextMenus"
  ],
  "background": {
    "scripts": [
      "dist/background.js"
    ]
  },
  "options_ui": {
    "page": "setting/options.html",
    "browser_style": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "cneyhn@gmail.com"
    }
  }
}