Examine source code of Twine Enhancer

{
  "name": "Twine Enhancer",
  "short_name": "Twine++",
  "manifest_version": 2,
  "version": "1.8.4",
  "description": "__MSG_extensionDescription__",
  "homepage_url": "https://github.com/hogart/twine-enhancer",
  "default_locale": "en",
  "icons": {
    "16": "./icons/16.png",
    "48": "./icons/48.png",
    "128": "./icons/128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "7a6c3c31de8b5b7389304c652dfd8c930f4bb98a@twine-enhancer",
      "strict_min_version": "57.0"
    }
  },
  "permissions": [
    "storage"
  ],
  "background": {
    "scripts": [
      "background/background.bundle.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "http://twinery.org/2/*",
        "https://twinery.org/2/*"
      ],
      "js": [
        "./content/content.bundle.js"
      ],
      "css": [
        "./content/common.css",
        "./content/webColors.css",
        "./content/biggerEditors.css",
        "./content/neaterPassages.css",
        "./content/toolbarButtons.css"
      ]
    }
  ],
  "options_ui": {
    "page": "options/options.html",
    "chrome_style": true
  }
}