Examine source code of amogusify

{
  "manifest_version": 2,
  "name": "amogusify",
  "description": "replaces all occurrences of the word among with an amogus image",
  "version": "1.4",
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ],
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "amogus.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "amogus@nsood.in",
      "strict_min_version": "90.0"
    }
  }
}