Examine source code of SEO Audit Pro

{
  "manifest_version": 3,
  "name": "SEO Audit Pro",
  "version": "4.1",
  "description": "SEO audit: metadata, headings, links, images, schema, social preview, web vitals, accessibility & PDF reports. 100% free.",
  "homepage_url": "https://github.com/robuls4o/seo-audit-pro",
  "icons": {
    "16": "icon16.png",
    "32": "icon32.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "permissions": [
    "activeTab",
    "scripting",
    "storage",
    "webNavigation"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "seoauditpro@extension",
      "strict_min_version": "128.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self'; style-src 'self' 'unsafe-inline'; font-src 'self'"
  },
  "action": {
    "default_popup": "popup.html",
    "default_title": "SEO Audit Pro",
    "default_icon": {
      "16": "icon16.png",
      "32": "icon32.png",
      "48": "icon48.png",
      "128": "icon128.png"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ]
}