Examine source code of Media Queue

{
  "description": "Adds a browser action icon to the toolbar. Click on the icon to add pages to a queue, or view the current queue",
  "manifest_version": 2,
  "name": "Media Queue",
  "version": "1.1",
  "icons": {
    "48": "icons/queue-48.png"
  },
  "permissions": [
    "tabs",
    "storage",
    "contextMenus"
  ],
  "browser_action": {
    "default_icon": "icons/queue-48.png",
    "default_title": "Media Queue",
    "default_popup": "popup/popup.html"
  },
  "background": {
    "page": "background/background.html"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/watch*"
      ],
      "js": [
        "content/youtube-autoplay.js"
      ]
    }
  ],
  "commands": {
    "next-item-command": {
      "suggested_key": {
        "default": "Ctrl+Shift+Q"
      },
      "description": "Navigate to the next item in the queue"
    },
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Ctrl+Shift+1"
      }
    }
  }
}