Examine source code of NihongoAutoTracker

{
  "manifest_version": 2,
  "name": "NihongoAutoTracker",
  "description": "An unofficial NihongoTracker extension to automate your Japanese immersion logging.",
  "version": "4.3.0",
  "icons": {
    "16": "icon/16.png",
    "32": "icon/32.png",
    "48": "icon/48.png",
    "96": "icon/96.png",
    "128": "icon/128.png"
  },
  "permissions": [
    "storage",
    "contextMenus",
    "notifications",
    "tabs",
    "alarms",
    "scripting",
    "activeTab",
    "https://nihongotracker.app/*",
    "https://*.nihongotracker.app/*",
    "https://api.trakt.tv/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "nihongo-auto-tracker@nta.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_title": "NihongoAutoTracker",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "all_frames": true,
      "css": [
        "content-scripts/text-tracker.css"
      ],
      "js": [
        "content-scripts/text-tracker.js"
      ]
    },
    {
      "matches": [
        "*://*.animekai.to/*",
        "*://*.crunchyroll.com/*",
        "*://*.youtube.com/*",
        "*://music.youtube.com/*"
      ],
      "css": [
        "content-scripts/video-tracker.css"
      ],
      "js": [
        "content-scripts/video-tracker.js"
      ]
    },
    {
      "matches": [
        "*://*.youtube.com/*",
        "*://music.youtube.com/*"
      ],
      "run_at": "document_start",
      "js": [
        "content-scripts/youtube-player-inject.js"
      ],
      "world": "MAIN"
    }
  ]
}