@Override
  protected @NotNull ModCommand perform(@NotNull ActionContext context, @NotNull PsiClass anInterface) {
    final Collection<PsiClass> inheritors = ClassInheritorsSearch.search(anInterface, anInterface.getUseScope(), false).findAll();
    final Map<PsiElement, ModShowConflicts.Conflict> conflicts =
      IntentionPreviewUtils.isIntentionPreviewActive() ? Map.of() : getConflicts(anInterface, inheritors);
    return showConflicts(conflicts)
      .andThen(psiUpdate(anInterface, (writableInterface, updater) -> convertInterfaceToClass(writableInterface, inheritors, updater)));
  }
@Override
  protected @NotNull ModCommand perform(@NotNull ActionContext context, @NotNull PsiClass anInterface)