Tell me why ConverterParameter falls out with the error "A 'Binding' can only be set on a DependencyProperty of a DependencyObject"?
<TextBlock Tag="{Binding First}"> <TextBlock.IsEnabled> <Binding Path="Second" Converter="{StaticResource FirstAndSecondToBoolConverter}" ConverterParameter="{Binding RelativeSource={RelativeSource Self}, Path=Tag}"/> </TextBlock.IsEnabled> </TextBlock>