Examine source code of Hard Refresh

{
  "manifest_version": 2,
  "name": "Hard Refresh",
  "version": "1.0",
  "permissions": [],
  "description": "Perform a hard refresh when clicking the extension icon.",
  "icons": {
    "48": "icons/refersh.svg"
  },
  "browser_action": {
    "default_icon": "icons/refersh.svg",
    "default_title": "Hard Refresh"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{8b9f57f0-9cae-48c1-8b64-c137b2cc5516}"
    }
  }
}