Examine source code of Scheduler Enhancer ex

{
  "manifest_version": 2,
  "name": "Scheduler Enhancer",
  "version": "1.0",
  "description": "A simple add-on to schedule theme changes.",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icon.png"
    }
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{c65ea9b7-9015-4db9-ad4a-b10019f55d59}"
    }
  }
}