When replacing a string within a run that is not the first element in the paragraph an unexpected behavior occurs.
These are the known cases:
- System.ArgumentOutOfRangeException: 'Index and length must refer to a location within the string. Parameter name: length'
- System.InvalidCastException: 'Unable to cast object of type <<type>> to type 'Telerik.Windows.Documents.Flow.Model.Run'.'
- Shifted text.