Examine source code of Shortlet - Tinker with Websites

{
  "manifest_version": 3,
  "version": "1",
  "name": "Shortlet - Tinker with Websites",
  "description": "Shortlet is a framework to configure and launch small hacks for the web.",
  "browser_specific_settings": {
    "gecko": {
      "id": "shortlet@psu"
    }
  },
  "action": {
    "default_icon": {
      "256": "icon.png"
    },
    "default_title": "Shortlet - Tinker with Websites"
  },
  "icons": {
    "256": "icon.png"
  },
  "background": {
    "service_worker": "shortlet/background.js",
    "scripts": [
      "shortlet/background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "css": [
        "command-pal/theme-dark.css",
        "command-pal/theme-shortlet.css",
        "shortlet/actions.css"
      ],
      "js": [
        "shortlet/MiniQueue.js",
        "shortlet/ShortletAPI.js",
        "command-pal/CommandPal.js",
        "shortlet/Shortlet.js"
      ],
      "run_at": "document_idle",
      "match_about_blank": true
    }
  ],
  "options_ui": {
    "page": "options/index.html",
    "open_in_tab": true
  },
  "permissions": [
    "scripting",
    "activeTab",
    "storage"
  ],
  "host_permissions": [
    "<all_urls>"
  ]
}