Staff Guide: Known issue reported for Ultra Documents.
Blackboard Known Issue article: 000077035
When you type content into a table within a Blackboard Document, the content sometimes disappears after the table has been saved.
Planned fix
Blackboard plans to fix this bug but does not yet have a date.
Workaround
We recommend you create any table content in a Word table and then copy and paste the table into the Blackboard Document. If any content is lost, you can re-copy it from Word.