Examine source code of YouTube Resume

{
  "manifest_version": 3,
  "name": "YouTube Resume",
  "version": "1.0.1",
  "description": "Save and resume YouTube videos at the last watched time.",
  "permissions": [
    "storage",
    "tabs",
    "scripting"
  ],
  "host_permissions": [
    "*://www.youtube.com/watch*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "service_worker": "background.js"
  },
  "action": {
    "default_title": "YouTube Resume",
    "default_popup": "popup.html"
  },
  "icons": {
    "32": "icons/blink.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.youtube.com/watch*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "youtube-resume95@example.com"
    }
  }
}