Note - This is not part of the OOXML spec
Not OOXML spec - Not support
Shrinks text to fit within the bounding area
Visible means that the text will attempt to be visible on overflow. It can still be obscured (either z-index, or another blocking element) or fall out of the viewport.
Wrap text to keep within the left right margins but may overflow vertically.
The behavior of the text when it exceeds the size of the bounding box.