message: Don't show broken composer format bar when selection is whitespace
diff: @@ -449,12 +449,11 @@ export default class BasicMessageEditor extends React.Component<IProps, IState>
  const selection = document.getSelection();
  if (this.hasTextSelected && selection.isCollapsed) {
  this.hasTextSelected = false;
  - if (this.formatBarRef.current) {
  - this.formatBarRef.current.hide();
  - }
  + this.formatBarRef.current?.hide();
  } else if (!selection.isCollapsed && !isEmpty) {
  this.hasTextSelected = true;
  - if (this.formatBarRef.current && this.state.useMarkdown) {
  + const range = getRangeForSelection(this.editorRef.current, this.props.model, selection);
  + if (this.formatBarRef.current && this.state.useMarkdown && !!range.text.trim()) {
  const selectionRect = selection.getRangeAt(0).getBoundingClientRect();
  this.formatBarRef.current.showAt(selectionRect);
  }
  