Examine source code of Night Atlas

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 3,
  "name": "Night Atlas",
  "version": "20.6",
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icon16.png",
      "48": "icon48.png",
      "128": "icon128.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a30714f1-68dc-4460-aa6c-17426227cf26}",
      "strict_min_version": "109.0"
    }
  },
  "permissions": [
    "storage",
    "scripting",
    "tabs"
  ],
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "host_permissions": [
    "*://abhs.daymap.net/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://abhs.daymap.net/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start"
    }
  ]
}