Examine source code of Mindful Browsing

{
  "manifest_version": 2,
  "name": "Mindful Browsing",
  "version": "1.0",
  "description": "Helps you stay mindful of your browsing time by reminding you to take breaks.",
  "icons": {
    "48": "icons/mindful-icon-48.png"
  },
  "permissions": [
    "alarms",
    "notifications"
  ],
  "browser_action": {
    "default_icon": "icons/mindful-icon-48.png",
    "default_popup": "mindful-popup.html",
    "default_title": "Mindful Browsing"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{6aead64c-3779-4d9a-a611-9cc32cccf061}"
    }
  }
}