ValidationAssist.Suppress does not affect textbox underline

I am using the following style to suppress validation on disabled textboxes.

    <Style x:Key="DefaultTextBox" TargetType="{x:Type TextBox}" BasedOn="{StaticResource MaterialDesignTextBox}">
        <Style.Triggers>
            <!-- Remove the errors when the control is disabled. -->
            <Trigger Property="IsEnabled" Value="False">
                <Setter Property="materialDesign:ValidationAssist.Suppress" Value="True"/>
                <!--<Setter Property="BorderBrush" Value="{StaticResource MaterialDesignTextBoxBorder}"/>-->
            </Trigger>
        </Style.Triggers>
    </Style>

Here is the result of that:

The red underline is still applied to the disabled textbox. The Error text is correctly hidden.

I worked around this by using the commented out setter for the BorderBrush. This is mostly just to make the behavior consistent with other controls. The Combobox does not require the workaround. I haven't tested any other controls either so it may be worth checking each one.

Commencez par reproduire le style XAML fourni avec un TextBox désactivé présentant une erreur de validation, puis comparez son style de validation au comportement de ComboBox. Suivez le modèle ou le style de validation de TextBox et vérifiez que la suppression de la validation supprime également le soulignement rouge tout en conservant le texte d’erreur masqué.