@Override
  protected @NotNull ModCommand perform(@NotNull ActionContext context, @NotNull PsiIdentifier startElement) {
    PsiClass psiClass = PsiTreeUtil.getParentOfType(startElement, PsiClass.class);
    if (psiClass == null) return ModCommand.nop();
    PsiJavaFile psiJavaFile = tryCast(psiClass.getContainingFile(), PsiJavaFile.class);
    if (psiJavaFile == null) return ModCommand.nop();
    Set<PsiClass> permittedClasses = ContainerUtil.map2Set(psiClass.getPermitsListTypes(), PsiClassType::resolve);
    return getMissingInheritors(psiJavaFile, psiClass, permittedClasses);
  }
@Override
  protected @NotNull ModCommand perform(@NotNull ActionContext context, @NotNull PsiIdentifier startElement)