Examine source code of Hard drive icon

{
  "manifest_version": 2,
  "name": "Hard drive icon",
  "version": "1.0",
  "description": "The hard drive icon means storing sound, images, characters, documents... in devices such as phones, computers and other electronic devices.",
  "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": "{be261c18-3b9d-4d0b-b24e-6d7a42a136c1}"
    }
  }
}