Examine source code of Marx-Mode

{
  "manifest_version": 2,
  "name": "Marx-Mode",
  "version": "1.1.25",
  "description": "Extension for restyling Conor Mcbride’s Marx system.",
  "icons": {
    "128": "icon128.png"
  },
  "content_scripts": [
    {
      "css": [
        "marx.css"
      ],
      "matches": [
        "https://personal.cis.strath.ac.uk/conor.mcbride/shib/Marx/*"
      ]
    }
  ]
}