Examine source code of YouTube (un)cookify

{
  "manifest_version": 2,
  "name": "YouTube (un)cookify",
  "version": "1.1",
  "description": "Quickly switch context to watch YouTube video without impacting your watch history!",
  "author": "Bertrand Lemasle",
  "homepage_url": "https://github.com/blemasle/youtube-uncookify",
  "icons": {
    "16": "icons/icon-16.png",
    "64": "icons/icon-64.png"
  },
  "permissions": [
    "tabs",
    "contextMenus"
  ],
  "page_action": {
    "default_title": "YouTube (un)cookify",
    "default_icon": {
      "19": "icons/icon-19.png",
      "38": "icons/icon-38.png"
    },
    "show_matches": [
      "https://www.youtube.com/watch?v=*",
      "https://www.youtube-nocookie.com/embed/*"
    ]
  },
  "background": {
    "scripts": [
      "uncookify.js"
    ]
  },
  "commands": {
    "_execute_page_action": {
      "suggested_key": {
        "default": "Ctrl+Shift+Y"
      }
    }
  }
}