Examine source code of WikipediaMobileOnly

{
  "manifest_version": 2,
  "name": "WikipediaMobileOnly",
  "version": "1.0",
  "description": "Automatically redirects You from the normal Wikipedia site to the mobile version because, well, it looks better",
  "icons": {
    "48": "icons/wikipedia48.ico"
  },
  "applications": {
    "gecko": {
      "id": "kppublic@posteo.de"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.wikipedia.org/*"
      ],
      "js": [
        "main.js"
      ]
    }
  ]
}