Given a #GtkSelectionData object holding a list of targets, determines if any of the targets in @targets can be used to provide rich text.
a #GtkTextBuffer
Return: %TRUE if @selection_data holds a list of targets, and a suitable target for rich text is included, otherwise %FALSE.
2.10
See Implementation
Given a #GtkSelectionData object holding a list of targets, determines if any of the targets in @targets can be used to provide rich text.