Examine source code of Disable Twitter Feed

{
  "manifest_version": 2,
  "name": "Disable Twitter Feed",
  "version": "1.0",
  "description": "Removes the timeline on Twitter's homepage.",
  "content_scripts": [
    {
      "matches": [
        "*://*.twitter.com/*"
      ],
      "js": [
        "disablefeed.js"
      ],
      "run_at": "document_start"
    }
  ],
  "icons": {
    "48": "icon.png",
    "96": "icon@2x.png"
  }
}