Examine source code of Better Youtube Captions

{
  "manifest_version": 2,
  "name": "YouTube Transcript Viewer",
  "version": "1.0",
  "description": "Display YouTube transcripts as customizable subtitles directly on videos.",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_popup": "options.html"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{0cb278df-6770-4acb-af3a-ece198201fb2}"
    }
  }
}