Problematic tests list (48 rows):
bugs.core_1746_test  Expression index can be created while doing inserts into table
bugs.core_1894_test  Circular dependencies between computed fields crash the engine
bugs.core_2140_test  Error messages after parameters substitution contains '\n' characters instead of line break
bugs.core_3450_test  Inefficient optimization (regression)
bugs.core_3610_test  Can insert DUPLICATE keys in UNIQUE index
bugs.core_3672_test  computed index by SUBSTRING function for long columns
bugs.core_3691_test  Missing constraint name in foreign key error message in FB 2.1.4
bugs.core_4386_test  Report more details for "object in use" errors
bugs.core_4754_test  Bugcheck 167 (invalid SEND request) while working with GTT from several attachments (using EXECUTE STATEMENT ... ON EXTERNAL and different roles)
bugs.core_4819_test  EXECUTE PROCEDURE's RETURNING_VALUES and EXECUTE STATEMENT's INTO does not check validity of assignments targets leading to bugcheck
bugs.core_4923_test  Add ability to track domains rename in DDL triggers
bugs.core_4933_test  Add better transaction control to isql
bugs.core_4937_test  View/subselect with "union" does not use computed index
bugs.core_5074_test  Lost the charset ID in selection of array element
bugs.core_5161_test  Unique index could be created on non-unique data
bugs.core_5275_test  Expression index may become inconsistent if CREATE INDEX was interrupted after b-tree creation but before commiting
bugs.core_5410_test  Dependencies are not stored when using some type of contructions in subroutines
bugs.core_5481_test  Available indices are not used in some cases if ORDER BY expression is a filtered one
bugs.core_5488_session_idle_test  Timeouts for running SQL statements and idle connections
bugs.core_5606_test  Add expression index name to exception message if computation failed
bugs.core_5618_test  Part of the pages of the second level blobs is not released when deleting relations
bugs.gh_7106_test  Wrong detection of must-be-delimited user names
bugs.gh_7200_test  DROP DATABASE lead FB to hang if it is issued while DB encrypting/decrypting is in progress
bugs.gh_7288_test  Server crashes when working with DSQL savepoints
bugs.gh_7545_test  Server crash on some LockMemSize values
bugs.gh_8391_test  gbak: Incorrect total statistics for restore
bugs.gh_8644_test  Connection error via Loopback provider if it's the first in the Providers parameter
functional.basic.isql.test_07  Add REPLICA MODE to the output of the isql SHOW DATABASE command
functional.basic.isql.test_08  ISQL showing publication status
functional.replication.test_blob_characters_garbled_when_conn_charset_differs  Characters are garbled when replicating fields with type BLOB SUB_TYPE TEXT if the character set of the connection and the field are different
functional.replication.test_blob_not_found_in_rw_replica_if_target_row_exists  Error "BLOB is not found" while replication converts INSERT into UPDATE for a conflicting record
functional.replication.test_blob_segments_longer_32kb_are_not_replicated  Problem with replication of BLOB segments longer than 32KB
functional.replication.test_bugcheck_in_rw_replica_after_conflicting_insert  Bugcheck 183 (wrong record length) could happen on replica database after UK violation on insert
functional.replication.test_dblevel_triggers_must_not_fire_on_replica  Replica DB must not fire DB-level triggers but their activity on master must be eventually seen in replica
functional.replication.test_ddl_triggers_must_not_fire_on_replica  DDL-triggers must fire only on master DB
functional.replication.test_disallow_rdb_backup_history_replication  Disallow replication of RDB$BACKUP_HISTORY
functional.replication.test_duplicates_in_rw_replica_after_conflicting_insert  Conflicting INSERT propagated into a read-write replica may cause duplicate records to appear
functional.replication.test_failed_ddl_commands_can_be_replicated  Failed DDL commands can be replicated
functional.replication.test_generator_could_not_be_transferred_to_replica  Generator values may not replicate after commit
functional.replication.test_invalid_msg_if_target_db_has_no_replica_flag  Invalid message in replication.log (and possibly crash in the case of synchronous replication) when the target DB has no its "replica" flag set
functional.replication.test_lookup_problems_for_intl_data_in_unique_indices  Lookup problems for INTL strings in unique indices
functional.replication.test_make_async_reinit_reliable  Make asynchronous replica re-initialization reliable #8324
functional.replication.test_shutdown_during_applying_segments_leads_to_crash  Crash or hang while shutting down the replica database if segments are being applied
functional.replication.test_some_updates_crash_server_on_replica_side  Some updates can crash Firebird server on replica side
functional.replication.test_sync_replica_allow_spaces_in_username_or_password  Leading, trailing or inner space character specified in 'sync_replica' must not cause error
functional.replication.test_sync_replica_server_hangs_on_disconnect  Synchronous replication hangs on disconnect [CORE6497]
functional.replication.test_uk_violation_in_rw_repl_if_constraint_name_is_used  PK/UK violation error raises in RW replica if constraint name is used to check uniqueness instead of index name
functional.replication.test_updating_blob_with_empty_string_stops_replication  Replication gets stuck due to "Blob xxx.xx is not found for table xxx" error

This list is the same for:
6.0.0.1847 2026.03.20 a420b530  SS