Designer paper can be set to invalid state by draggin sub components of vaadin-login-form

Steps to reproduce

With the attached layout it is possible to drag-and-drop sub-components of the vaadin-login-form. Designer is visually broken after dnd operations. Refreshing returns the correct rendering.

IDE, Designer and OS version

Designer 4.4.1, Windows 10, Designer in Chrome

File

import { PolymerElement } from "@polymer/polymer/polymer-element.js";
import { html } from "@polymer/polymer/lib/utils/html-tag.js";
import "@vaadin/vaadin-lumo-styles/all-imports.js";
import '@vaadin/vaadin-login/src/vaadin-login-form.js';

class LoginView extends PolymerElement {
  static get template() {
    return html`
<style include="shared-styles lumo-badge lumo-typography">
        :host {
          background-color: var(--lumo-contrast-10pct);
          display: block;
          height: 100%;
          overflow: auto;
        }

        .card {
          border-radius: var(--lumo-border-radius);
          box-shadow: var(--lumo-box-shadow-m);
          margin: var(--lumo-space-l) auto;
          overflow: hidden;
          width: calc(var(--lumo-size-m) * 10);
        }

        .brand {
          background-color: var(--lumo-primary-color);
          box-sizing: border-box;
          display: flex;
          flex-direction: column;
          justify-content: flex-end;
          min-height: calc(var(--lumo-size-m) * 5);
          padding: var(--lumo-space-l);
        }

        h1 {
          color: var(--lumo-primary-contrast-color);
          margin: 0;
        }

        span {
          color: var(--lumo-tint-70pct);
        }

        vaadin-login-form {
          display: flex;
        }
      </style>
<div class="card">
 <div class="brand">
  <h1>App name</h1>
  <span>Application description</span>
 </div>
 <vaadin-login-form></vaadin-login-form>
</div>
`;
  }

  static get is() {
    return "login-view";
  }

  static get properties() {
    return {
      // Declare your properties here.
    };
  }
}

customElements.define(LoginView.is, LoginView);

Hello there!

It looks like this issue hasn't progressed lately. There are so many issues that we just can't deal them all within a reasonable timeframe.

There are a few things you could help to get things rolling on this issue (this is an automated message, so expect that some of these are already in use):

Check if the issue is still valid for the latest version. There are many duplicates in our issue tracker, so it is possible that the issue is already tackled.
Provide more details how to reproduce the issue.
Explain why it is important to get this issue fixed and politely draw others attention to it e.g. via the forum or social media.
Add a reduced test case about the issue, so it is easier for somebody to start working on a solution.
If the issue is clearly a bug, use the Warranty in your Vaadin subscription to raise its priority.

Thanks again for your contributions! Even though we haven't been able to get this issue fixed, we hope you to report your findings and enhancement ideas in the future too!

vaadin / designer