Examine source code of @FindBy

{
  "manifest_version": 2,
  "name": "@FindBy",
  "version": "1.3",
  "description": "Generates cssSelector and xPath for Selenium",
  "author": "Vigneshwaran Gopalan",
  "background": {
    "scripts": [
      "./jscripts/FindBy_eventPage.js"
    ]
  },
  "permissions": [
    "contextMenus",
    "storage"
  ],
  "web_accessible_resources": [
    "/icons/*.png"
  ],
  "icons": {
    "16": "./icons/FindBy.png",
    "48": "./icons/FindBy.png",
    "128": "./icons/FindBy.png"
  },
  "content_scripts": [
    {
      "all_frames": true,
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "./jscripts/jquery-3.5.1.min.js",
        "./jscripts/FindBy_cs.js",
        "./jscripts/FindByPopupUI.js"
      ],
      "css": [
        "/css/FindByPopup.css",
        "/css/w3.css"
      ]
    }
  ]
}