Hi,

The RichTextBox control does not expose a single text property that you could use for a spellcheck target binding, like for example the Text property of the regular TextBox. So , a possible way to do that is to add a spellcheck target for each text element in the RichTextbox. This will ensure preserving the correct formatting, but you'll have to spellcheck every Inline as a different spell-check target.

Attached is a sample that demonstrates that.

Hope that helps,