Examine source code of NoFB

{
  "manifest_version": 2,
  "name": "NoFB",
  "version": "1.1resigned1",
  "description": "Redirects you from facebook to mathisfun.com",
  "icons": {
    "48": "icons/nofb.png"
  },
  "applications": {
    "gecko": {
      "id": "app2tejas@appsforfun"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.facebook.com/*",
        "*://*.twitter.com/*"
      ],
      "js": [
        "nofb.js"
      ]
    }
  ]
}