Examine source code of Cube icon

{
  "manifest_version": 2,
  "name": "Cube icon",
  "version": "1.0",
  "description": "Cube icons are commonly used to represent 3D objects or basic geometric elements in design, modeling, or geometry learning software.",
  "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": "{b2b8b23e-201c-4b94-8239-5065433aa424}"
    }
  }
}