app/assets/javascripts/spina/controllers/parent_pages_controller.js
import { Controller } from "@hotwired/stimulus"
export default class extends Controller {
static get targets() {
return ["frame"]
}
update(event) {
let select = event.currentTarget
let option = select.options[select.selectedIndex]
let src = option.dataset.parentPagesUrl
this.frameTarget.src = src
}
}