Examine source code of Find in Files

{
  "name": "Find in Files",
  "description": "Full-text for files. Instant find text in files. Search word in pdf, txt, csv, json, html, ...",
  "version": "1.9",
  "icons": {
    "16": "images/16x16.png",
    "48": "images/48x48.png",
    "128": "images/128x128.png"
  },
  "homepage_url": "https://app-fif.web.app/",
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "permissions": [
    "tabs"
  ],
  "browser_action": {
    "default_title": "Find in Files"
  },
  "manifest_version": 2
}