Upon saving an Edit to an existing Study Area, the Study Area is removed from the Study Area tab datagrid. I confirmed in the database that the STUDY_AREAS.PROJECT_ID field is actually being nulled upon save.
To recreate:
Select a project with an existing study area, enable editing, and open the Study Area editing popup window.
Click Apply to save edits (no edit actually necessary).
The Study Area is removed from the data grid. In the database, the relationship key is nulled.
Upon saving an Edit to an existing Study Area, the Study Area is removed from the Study Area tab datagrid. I confirmed in the database that the STUDY_AREAS.PROJECT_ID field is actually being nulled upon save.
To recreate: