SQL - Redshift code completion stopped working, can't find schema

Until the latest update, or maybe the one before, integration between the SQL editor and Redshift was pretty good. I could highlight a SQL statement and run it, and code completion worked for table names.

Now, however, with the Database Navigator plugin, though I can connect to Redshift OK, the editor can't see any of the Redshift schema. When I click on the Schema dropdown all I see is "nothing here". And, frustratingly, even if I explicitly type in a schema name, I can't run any SQL from the editor.

So it appears that something has changed in the most recent versions of Pycharm, and not for the better.

Any advice appreciated.