If you try to paste text in the RadMaskedTextInput control using the default ContextMenu, after the Clear button is pressed, the Paste command is not working as expected.
Fixed in R1 2015.
Du0plication:

When MaskedNumericInput (or Currency) control is inside ScrollViewer, HorizontalAlignment is Stretch and HorizontalContentAlignment is NOT Left , clicking in control does not focus it.
You must click close to the Value in order to focus successfully.
This should work like it works when the HorizontalAlignment is Left.
This is reproducible only in Silverlight.

When the MaskedInput controls are wrapped in a ScrollViewer and the validation tooltip of one of the controls is displayed, it doesn't close while scrolling with the scroll bars.