Examine source code of Better Lyrics (Lyrics for Youtube Music)

{
  "manifest_version": 3,
  "version": "2.3.1",
  "default_locale": "en",
  "name": "Better Lyrics (Lyrics for Youtube Music)",
  "description": "__MSG_extensionDescription__",
  "homepage_url": "https://betterlyrics.org",
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "512": "icons/icon-512.png"
  },
  "host_permissions": [
    "*://music.youtube.com/*"
  ],
  "permissions": [
    "storage",
    "alarms"
  ],
  "externally_connectable": {
    "matches": [
      "https://unison.boidu.dev/*",
      "https://blrcunison.vercel.app/*"
    ]
  },
  "optional_permissions": [
    "downloads"
  ],
  "optional_host_permissions": [],
  "content_security_policy": {
    "extension_pages": "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline' https://api.fontshare.com https://fonts.googleapis.com; font-src 'self' data: https://cdn.fontshare.com https://fonts.gstatic.com; img-src 'self' data: https://blrcunison.vercel.app https://boidu.dev https://betterlyrics.org https://raw.githubusercontent.com https://placehold.co; connect-src https://unison.boidu.dev https://raw.githubusercontent.com https://api.github.com https://better-lyrics-themes-api.boidu.dev; frame-src https://better-lyrics-themes-api.boidu.dev;"
  },
  "options_ui": {
    "page": "options_ui/page.html",
    "open_in_tab": false
  },
  "web_accessible_resources": [
    {
      "resources": [
        "*.js.map",
        "css/blyrics/*.css",
        "css/disablestylizedanimations.css",
        "css/themes/*.css",
        "css/themesong.css",
        "css/ytmusic/*.css",
        "images/icons/shaders.png",
        "pages/marketplace.html",
        "pages/standalone-editor.html",
        "pages/unison.html"
      ],
      "matches": [
        "*://music.youtube.com/*"
      ]
    },
    {
      "resources": [
        "pages/auth.html"
      ],
      "matches": [
        "https://blrcunison.vercel.app/*",
        "https://unison.boidu.dev/*"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "betterlyrics@boidu.dev",
      "strict_min_version": "100.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://music.youtube.com/*"
      ],
      "js": [
        "content_scripts/content-0.js"
      ],
      "run_at": "document_start",
      "world": "ISOLATED",
      "css": []
    },
    {
      "matches": [
        "*://music.youtube.com/*"
      ],
      "js": [
        "earlyInject.js"
      ],
      "run_at": "document_start",
      "world": "MAIN",
      "css": []
    },
    {
      "matches": [
        "*://music.youtube.com/*"
      ],
      "js": [
        "script.js"
      ],
      "run_at": "document_end",
      "world": "MAIN",
      "css": []
    }
  ],
  "action": {
    "default_popup": "action/default_popup.html"
  },
  "version_name": "2.3.1"
}