Examine source code of helmi's Auto Refresh

{
  "manifest_version": 2,
  "name": "helmi's Auto Refresh",
  "version": "1.1",
  "description": "Helmi's tool for auto-refreshing pages with countdown, click automation, and smart reload.",
  "icons": {
    "48": "icon.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "permissions": [
    "tabs",
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{5674b875-f0ae-4cb9-9af4-ba47bef15841}"
    }
  }
}