Examine source code of Content MathML Polyfill

{
  "manifest_version": 2,
  "name": "Content MathML Polyfill",
  "version": "2.1resigned1",
  "description": "Converter from content MathML to presentation MathML",
  "author": "Frédéric Wang",
  "homepage_url": "https://github.com/fred-wang/webextension-content-mathml-polyfill",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "all_frames": true,
      "js": [
        "content-to-presentation.js"
      ],
      "web_accessible_resources": [
        "content-to-presentation.xsl"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "MathML-ctop@mozilla.com"
    }
  }
}