Examine source code of Anti Doom Scroll Timer

{
  "manifest_version": 2,
  "name": "Anti-Doom Scroll Timer",
  "version": "1.31",
  "browser_specific_settings": {
    "gecko": {
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "id": "{60c79389-64ea-4988-a75f-e39a90d62fad}"
    }
  },
  "description": "Prevents doomscrolling on YouTube, Facebook, X, TikTok, Reddit, Pinterest, and Instagram. By promping a timer before entering the website.",
  "permissions": [
    "tabs",
    "*://*.youtube.com/*",
    "*://*.facebook.com/*",
    "*://*.twitter.com/*",
    "*://*.x.com/*",
    "*://*.tiktok.com/*",
    "*://*.reddit.com/*",
    "*://*.instagram.com/*",
    "*://*.pinterest.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*",
        "*://*.facebook.com/*",
        "*://*.twitter.com/*",
        "*://*.x.com/*",
        "*://*.tiktok.com/*",
        "*://*.instagram.com/*",
        "*://*.pinterest.com/*",
        "*://*.reddit.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ]
}