Examine source code of Grammar.com

{
  "manifest_version": 2,
  "name": "Grammar.com",
  "short_name": "Grammar.com",
  "version": "1.0.4resigned1",
  "description": "__MSG_appDesc__",
  "default_locale": "en",
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "64": "images/icon64.png",
    "128": "images/icon128.png"
  },
  "author": "STANDS4 LLC",
  "homepage_url": "http://www.grammar.com",
  "offline_enabled": false,
  "browser_action": {
    "default_icon": "images/icon48.png",
    "default_popup": "popup.html",
    "default_title": "__MSG_tooltip__",
    "browser_style": false
  },
  "permissions": [
    "activeTab",
    "storage",
    "contextMenus"
  ],
  "background": {
    "scripts": [
      "bs/background.js",
      "share/tools.js",
      "bs/common.js",
      "share/markup.js"
    ]
  },
  "web_accessible_resources": [
    "images/*",
    "**/*.js",
    "vendors/*",
    "popup.html"
  ],
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*",
        "file:///*"
      ],
      "js": [
        "vendors/jquery.min.js",
        "vendors/purify.js",
        "vendors/ally.min.js",
        "vendors/most.js",
        "vendors/featherlight/featherlight.js",
        "share/helpers.js",
        "share/tools.js",
        "share/markup.js",
        "cs/contentscript.js",
        "cs/textarea.js"
      ],
      "css": [
        "vendors/featherlight/featherlight.css",
        "css/lt-marker-style.css"
      ]
    },
    {
      "matches": [
        "http://www.grammar.com/*",
        "https://www.grammar.com/*"
      ],
      "js": [
        "cs/contentscript-lt.js"
      ]
    }
  ],
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Ctrl+Shift+Space"
      }
    }
  },
  "options_ui": {
    "page": "options.html",
    "chrome_style": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{9480fd84-81eb-4fa2-a77f-3e8d516fcee7}"
    }
  }
}