Examine source code of Makeup brush icon

{
  "manifest_version": 2,
  "name": "Makeup brush icon",
  "version": "1.0",
  "description": "Makeup brush icons often appear in beauty, spa, or cosmetic related designs.",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_icon": "icon.png",
    "default_popup": "popup.html",
    "default_title": "Click me!"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{73a5b4aa-5e4e-4e19-a425-bcfc965c90fa}"
    }
  }
}