Hi, rjames: I don't know how v12 handles this any different, but at least in earlier versions, I 'correct' for this using an auto-enter calculation (usually a custom function) that eliminates whatever formatting or other characteristics I don't want to allow the user to enter or paste.
For example, I have a custom function called _FontSizeCleaner( text ) =
TextFontRemove ( TextSizeRemove ( text ) )
This allows the user to type in any text, which then loses all its font size and font type formatting, leaving other formatting, such as style and color intact.
Use the text style formatting functions in whatever combination you need for the task at hand.
Thanks Erik - that's what I ended up finding in another forum as well.