+* If revision deletions were performed when the wiki was configured with
+ $wgActorTableSchemaMigrationStage SCHEMA_COMPAT_WRITE_BOTH and without
+ migrateActors.php having been run, the log_search table may contain rows with
+ empty values for "target_author_actor" which will prevent log searches for
+ revision deletions by target user from finding those log entries. These rows
+ may be corrected by (re-)running migrateActors.php.