Examine source code of ICTFM for YouTube

{
  "manifest_version": 2,
  "name": "I can think for myself (ICTFM)",
  "description": "Hide Context/propaganda boxes from YouTube videos.",
  "version": "1.0",
  "author": "Sam St-Pettersen",
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/*"
      ],
      "js": [
        "no_context_boxes.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{0ccd041e-d572-4ef7-9bdd-c5e3aac5df59}"
    }
  }
}