Examine source code of Reload Tabs

{
  "manifest_version": 2,
  "name": "Reload Tabs",
  "version": "1.0",
  "description": "Reload all open browser tabs.",
  "icons": {
    "16": "icons/16.png",
    "24": "icons/24.png",
    "32": "icons/32.png",
    "64": "icons/64.png",
    "128": "icons/128.png",
    "256": "icons/256.png",
    "512": "icons/512.png"
  },
  "browser_action": {
    "default_icon": "icons/64.png",
    "default_title": "Reload Tabs"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "activeTab",
    "contextMenus",
    "tabs"
  ]
}