Examine source code of Language Learning Time Tracker

{
  "manifest_version": 2,
  "name": "YouTube Language Watch Calendar",
  "version": "1.1.0",
  "description": "Tracks watched YouTube time, detects content language, and shows daily, weekly, and monthly totals in a calendar.",
  "permissions": [
    "storage",
    "alarms",
    "notifications",
    "tabs",
    "https://www.youtube.com/*",
    "https://m.youtube.com/*",
    "https://app.dreaming.com/*",
    "https://podcasts.apple.com/*",
    "https://open.spotify.com/*"
  ],
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "youtube-language-watch-calendar@local",
      "strict_min_version": "128.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "options_page": "settings.html",
  "browser_action": {
    "default_title": "YouTube Watch Calendar",
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/*",
        "https://m.youtube.com/*",
        "https://app.dreaming.com/*",
        "https://podcasts.apple.com/*",
        "https://open.spotify.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ]
}