Examine source code of youtube-sidebar

{
  "manifest_version": 2,
  "name": "youtube-sidebar",
  "description": "show youtube in sidebar",
  "version": "1.0",
  "browser_specific_settings": {
    "gecko": {
      "strict_min_version": "58.0",
      "id": "{4b4d2760-e87b-4653-8faf-7396dfea40d0}"
    }
  },
  "sidebar_action": {
    "default_icon": "icons/favicon.png",
    "default_title": "youtube Sidebar",
    "default_panel": "sidebar/panel.html"
  },
  "permissions": [
    "storage",
    "tabs"
  ]
}