Richtextbox control does not respond to touchscreen controls for scrolling and only highlights text instead

Nadie ha tomado este issue todavía.

### Bug explanation

I built a modern log interface for legacy chat software and use MaterialDesign to theme everything. I'm using the MaterialDesign Richtextbox style and when I try and enable the following:

```
ScrollViewer.CanContentScroll="True"
ScrollViewer.PanningMode="VerticalFirst"
Stylus.IsPressAndHoldEnabled="False"
Stylus.IsFlicksEnabled="False"
```

It still only highlights the text in the Richtextbox control when using touchscreen controls. Does this mean that I need to override the control template or is there something that I'm missing for this?

I've considered making changes to the MaterialDesign.Textbox.xaml prior to compile and adding the `CanContentScroll=True` there but not sure if that's going to fix it or not.

Does anyone have any suggestions for this? I have a Surface Pro that I'm testing on and I've had reports of it not working for others as well.

Please let me know if you need any further details or code, I'm happy to share.

Thanks!

### Version

5.1.0.0

Comienza reproduciendo el comportamiento de la pantalla táctil con el MaterialDesign Richtextbox style en un Surface Pro o una configuración WPF equivalente. Inspecciona MaterialDesign.Textbox.xaml y la plantilla de control para determinar si el ScrollViewer configurado y las propiedades de stylus llegan al Richtextbox. Se considera terminado cuando el desplazamiento táctil vertical funciona sin seleccionar texto y el resultado se ha verificado en la versión indicada en el informe o en una compilación actual.

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