Examine source code of Reuse Tabs

{
  "manifest_version": 2,
  "name": "Reuse Tabs",
  "version": "1.0.1",
  "description": "Avoid duplicate tabs with repeated URL by reusing and recycling existing tabs.",
  "permissions": [
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  },
  "browser_action": {
    "default_icon": {
      "16": "images/icon16.png",
      "48": "images/icon48.png",
      "128": "images/icon128.png"
    },
    "default_title": "Reuse Tabs"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4d5b282b-e4b4-450d-80fa-9253a3014b20}"
    }
  }
}