Examine source code of WebNowPlaying

{
  "manifest_version": 3,
  "name": "WebNowPlaying",
  "short_name": "WebNowPlaying",
  "description": "A browser extension that provides information and controls for media playing in the browser to external adapters.",
  "version": "3.1.0",
  "icons": {
    "128": "icons/icon-darkmode-128.png",
    "256": "icons/icon-darkmode-256.png"
  },
  "action": {
    "default_popup": "index.html",
    "default_title": "WebNowPlaying"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "content.js"
      ],
      "all_frames": true
    }
  ],
  "background": {
    "scripts": [
      "sw.js"
    ]
  },
  "permissions": [
    "storage"
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "injected.js"
      ],
      "matches": [
        "*://*/*"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{64b2c525-24ed-4c05-aed1-95ff9e6cef70}",
      "strict_min_version": "109.0"
    }
  },
  "content_security_policy": {
    "extension_pages": "default-src *; script-src 'self'; img-src data:;"
  }
}