This function unregisters a rich text format that was previously registered using gtk_text_buffer_register_serialize_format() or gtk_text_buffer_register_serialize_tagset() Since 2.10
a GdkAtom representing a registered rich text format.
See Implementation
This function unregisters a rich text format that was previously registered using gtk_text_buffer_register_serialize_format() or gtk_text_buffer_register_serialize_tagset() Since 2.10