void cleanup() {
    myHints.entrySet().removeIf(e -> {
      PsiElement anchor = e.getKey();
      DfaHint hint = e.getValue();
      if (hint.getTitle() == null) return true;
      if (!(anchor instanceof PsiExpression expr)) return false;
      CommonDataflow.DataflowResult result = CommonDataflow.getDataflowResult(expr);
      return result != null && result.getExpressionValues(expr).size() == 1;
    });
  }
void cleanup()