Examine source code of Move & Refresh

{
  "manifest_version": 2,
  "name": "Move & Refresh",
  "description": "Reminds you to take a short break and stretch",
  "version": "1.0",
  "permissions": [
    "notifications",
    "alarms",
    "storage",
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "move-refresh@example.com",
      "strict_min_version": "109.0"
    }
  },
  "browser_action": {
    "default_popup": "index.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "web_accessible_resources": [
    "images/football.png",
    "images/footballGate.png",
    "model/*"
  ]
}