message: Add fallback warning
diff: @@ -27,6 +27,7 @@ interface IProps extends Omit<BaseProps, "groupMember" | "matrixClient" | "child
  allLabel: string;
  specificLabel: string;
  noneLabel?: string;
  + warningMessage?: string;
  onFinished(success: boolean, reason?: string, rooms?: Room[]): void;
  spaceChildFilter?(child: Room): boolean;
  }
  @@ -37,6 +38,7 @@ const ConfirmSpaceUserActionDialog: React.FC<IProps> = ({
  allLabel,
  specificLabel,
  noneLabel,
  + warningMessage,
  onFinished,
  ...props
  }) => {
  @@ -59,6 +61,10 @@ const ConfirmSpaceUserActionDialog: React.FC<IProps> = ({
  SpaceName: () => <b>{ space.name }</b>,
  }) }
  </div>;
  + } else if (warningMessage) {
  + warning = <div className="mx_ConfirmSpaceUserActionDialog_warning">
  + { warningMessage }
  + </div>;
  }
  return (
  