In the Schema Browser, when choosing the Materialized view logs:
there are duplicates in materialized view logs (differing from the DBA_MVIEW_LOGS)
Toad looks into the SYS.DBA_SNAPSHOT_LOGS instead of SYS.DBA_MVIEW_LOGS.
Please use a select statement for SYS.DBA_MVIEW_LOGS in the SQL Editor.
Waiting for a fix to be released in a future version of Toad for Oracle.