Examine source code of Highlight Heading

{
  "version": "2.1",
  "description": "Let you make your SEO easier by highlighting the headings on every page.",
  "homepage_url": "https://github.com/KovalchukDanil0/HighlightHeadings.git",
  "background": {
    "page": "background.bundle.js"
  },
  "manifest_version": 3,
  "name": "Highlight Headings",
  "action": {
    "default_popup": "popup.html"
  },
  "icons": {
    "16": "icon-16.png",
    "32": "icon-32.png",
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "contentScript.bundle.js"
      ],
      "run_at": "document_end"
    }
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "permissions": [
    "storage",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "HighlightHeadings@gomofob.com",
      "strict_min_version": "109.0"
    }
  }
}