Examine source code of MathQuill for Gmail

{
  "manifest_version": 2,
  "name": "MathQuill for Gmail/Thunderbird",
  "version": "0.1.2",
  "description": "WYSIWYG editing of math in Gmail (and possibly other pages)",
  "homepage_url": "https://github.com/dominique-unruh/mathquill-for-gmail/wiki",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "applications": {
    "gecko": {
      "id": "mathquill-for-gmail@unruh.de"
    }
  },
  "icons": {
    "16": "icon-16.png",
    "32": "icon-32.png",
    "48": "icon-48.png",
    "64": "icon-64.png",
    "96": "icon-96.png",
    "128": "icon-128.png"
  },
  "browser_action": {
    "default_icon": {
      "16": "icon-16.png",
      "32": "icon-32.png",
      "48": "icon-48.png",
      "64": "icon-64.png",
      "96": "icon-96.png",
      "128": "icon-128.png"
    },
    "default_title": "MathQuill for Gmail",
    "default_popup": "toolbar-menu.html"
  },
  "options_ui": {
    "page": "options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "https://mail.google.com/mail/*",
        "https://inbox.google.com/*",
        "https://www.example.com/"
      ],
      "js": [
        "jquery.min.js",
        "mathquill.min.js",
        "browser-polyfill.min.js",
        "shared.js",
        "mathquill-for-gmail.js"
      ],
      "css": [
        "mathquill.css"
      ]
    }
  ]
}