docs: @OverrideOnDemand
    public void beforeAddRenderedMenuItem (@Nonnull final IWebPageExecutionContext aWPEC,
                                           @Nonnull final IMenuObject aMenuObj,
                                           @Nullable final IHCElement <?> aPreviousLI)
    {
      if (aMenuObj.getMenuObjectType () == EMenuObjectType.SEPARATOR && aPreviousLI != null)
        aPreviousLI.addStyle (CCSSProperties.MARGIN_BOTTOM.newValue ("1em"));
    }