Added example of modal route with issue

src/Umbraco.Web.UI.Client/examples/modal-routed/tabs/tab2.element.ts

@@ -0,0 +1,59 @@
+import { css, html, LitElement } from 'lit';
+import { customElement, state } from 'lit/decorators.js';
+import { UmbLitElement } from '@umbraco-cms/backoffice/lit-element';
+import { UmbTextStyles } from '@umbraco-cms/backoffice/style';
+import { UmbElementMixin } from '@umbraco-cms/backoffice/element-api';
+import { UmbModalRouteRegistrationController } from '@umbraco-cms/backoffice/router';
+import { EXAMPLE_ROUTED_MODAL } from './../modal/example-modal-token';
+
+@customElement('umb-dashboard-tab2')
+export class UmbDashboardTab2Element extends UmbElementMixin(LitElement) {
+
+	#workspaceModal?: UmbModalRouteRegistrationController;
+
+  @state()
+	_editLinkPath?: string;
+
+  constructor() {
+    super();
+
+    // Using workspace modal context
+    this.#workspaceModal?.destroy();
+      this.#workspaceModal = new UmbModalRouteRegistrationController(this, EXAMPLE_ROUTED_MODAL)
+        .addAdditionalPath('view/:entityKey')
+        .onSetup(() => {
+          return {
+						data: {},
+						value: {}
+					};
+        })
+        .observeRouteBuilder((routeBuilder) => {
+          this._editLinkPath = routeBuilder({entityKey : 'abc123'});
+        });
+    }
+
+  override render() {
+    return html`
+      <div>
+        <h2>tab 2</h2>
+				<p>This element hosts the UmbModalRouteRegistrationController</p>
+
+        <a href=${this._editLinkPath ?? ""}>Open modal</a>
+        <hr/>
+
+        Path: ${this._editLinkPath}
+      </div>
+    `
+
+  }
+
+	static override styles = [UmbTextStyles, css``];
+}
+
+export default UmbDashboardTab2Element
+
+declare global {
+	interface UmbDashboardTab2Element {
+		'umb-dashboard-tab2': UmbDashboardTab2Element;
+	}
+}