Examine source code of BulbaHelper

{
  "manifest_version": 2,
  "name": "BulbaHelper",
  "version": "1.1resigned1",
  "description": "Adds filter buttons to Bulbapedia",
  "content_scripts": [
    {
      "matches": [
        "*://bulbapedia.bulbagarden.net/wiki/*"
      ],
      "js": [
        "js/jquery-3.3.1.min.js",
        "js/bhelper.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{b24431fd-ddde-4de3-a0ab-60533625d4fd}"
    }
  }
}