message: react: Render panel content when it was expanded before,
diff: @@ -7,6 +7,7 @@ import { SurveyPanelBase } from "./panel-base";
  import { PanelModel } from "../panel";
  export class SurveyPanel extends SurveyPanelBase {
  + private hasBeenExpanded: boolean = false;
  constructor(props: any) {
  super(props);
  this.panelBase = props.element;
  @@ -38,7 +39,8 @@ export class SurveyPanel extends SurveyPanelBase {
  display: !this.panel.isCollapsed ? "block" : "none"
  };
  var content = null;
  - if (!this.panel.isCollapsed) {
  + if (!this.panel.isCollapsed || this.hasBeenExpanded) {
  + this.hasBeenExpanded = true;
  var rows = this.renderRows();
  content = this.renderContent(style, rows);
  }
  