sure/app/javascript/controllers/expandable_controller.js

import { Controller } from "@hotwired/stimulus";

// Connects to data-controller="expandable"
//
// Reopens a cramped card (a chart, a wide table) in a roomier modal, mirroring
// the dashboard cashflow expand button. The trigger lives outside the <dialog>,
// so it is out of scope for the DS--dialog controller's own actions — this thin
// wrapper bridges the two.
//
// Native <dialog> tracks the previously focused element across showModal() /
// close(), so focus returns to the expand button on its own.
export default class extends Controller {
  static targets = ["dialog"];

  open() {
    const dialog = this.hasDialogTarget
      ? this.dialogTarget
      : this.element.querySelector("dialog");

    if (!dialog || dialog.open) return;

    dialog.showModal();
  }
}