Problematic tests list (49 rows):
bugs.core_0883_test  The built-in BLR printer doesn't support all FB2 features
bugs.core_1152_test  Cannot erase a table with check constraints referencing more than a single columns
bugs.core_3690_dialect_3_test  Wrong warning message for ambiguous query
bugs.core_4302_addi_test  Lookup (or scan) in descending index could be very inefficient for some keys
bugs.core_4302_test  Lookup (or scan) in descending index could be very inefficient for some keys
bugs.core_4731_test  Prohibit an ability to issue DML or DDL statements on RDB$ tables (CORE-4731)
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_4937_test  View/subselect with "union" does not use computed index
bugs.core_5275_test  Expression index may become inconsistent if CREATE INDEX was interrupted after b-tree creation but before commiting
bugs.core_5383_test  Dependencies in Package not recognised
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.core_5737_test  Invalid parameters of gds transaction in ISQL
bugs.core_5921_test  Provide information about Global Commit Number, Commit Number of currently used database snapshot (if any) and Commit Numbers assigned to the committed transactions
bugs.core_6095_test  Extend trace record for COMMIT/ROLLBACK RETAINING to allow chaining of transaction ids
bugs.core_6166_test  Problems with long object names (> 255 bytes)
bugs.core_6300_test  Next attachment id, next statement id and some other additions [CORE-6300]
bugs.core_6444_test  Ability to query Firebird configuration using SQL
bugs.gh_0310_test  System table with keywords
bugs.gh_6802_test  When the statement timeout is set, it causes the lock manager to delay reporting deadlocks until timeout is expired
bugs.gh_6869_test  Domain CHECK-expression can be ignored when we DROP objects that are involved in it
bugs.gh_7050_test  Add table MON$COMPILED_STATEMENTS and columns
bugs.gh_7220_test  Dependencies of subroutines are not preserved after backup restore
bugs.gh_7304_test  Events in system attachments (like garbage collector) are not traced
bugs.gh_7398_test  Worst plan sort created to execute an indexed tables
bugs.gh_7426_test  Ensure the DDL trigger requests are cached
bugs.gh_7466_plans_tracking_test  Add COMPILE trace events - ability to see execution plan of every PSQL statement.
bugs.gh_7466_test  Add COMPILE trace events for procedures/functions/triggers
bugs.gh_7804_test  The partial index is not involved when filtering conditions through OR.
bugs.gh_7904_test  More realistic cardinality adjustments for unmatchable booleans // FB5 bad plan for query
bugs.gh_8077_test  Error "Too many recursion levels" does not stop execuition of code that uses ON DISCONNECT trigger (FB 4.x+)
bugs.gh_8161_test  Cardinality estimation should use primary record versions only
bugs.gh_8219_test  Database creation in 3.0.12, 4.0.5 and 5.0.1 slower than in previous releases
bugs.gh_8278_test  Avoid index lookup for a NULL key if the condition is known to always be FALSE in this case
bugs.gh_8661_test  Strange output from SHOW DEPENDENCIES command on 6.0
bugs.gh_8851_test  'Internal error' when calling outer procedure after deleting unused result variable from inner procedure
functional.arno.optimizer.test_opt_inner_join_05  INNER JOIN join order LIKE and STARTING WITH
functional.basic.isql.test_02  ISQL - SHOW SYSTEM TABLES
functional.basic.isql.test_03  ISQL - SHOW SYSTEM parameters
functional.gtcs.test_computed_fields_13  Computed fields
functional.gtcs.test_misplaced_collation_in_extracted_metadata  Misplaced collation when extracting metadata with isql
functional.gtcs.test_returning_01  Test of RETURNING clause: INSERT, UPDATE, MERGE.
functional.replication.test_ddl_triggers_must_not_fire_on_replica  DDL-triggers must fire only on master DB
functional.table.create.test_06  CREATE TABLE - two column with same name
functional.trigger.alter.test_alter_dml_basic  ALTER TRIGGER - basic checks for DML triggers
functional.trigger.database.test_transactioncommit_01  Trigger on commit transaction. See also CORE-645

This list is the same for:
6.0.0.1947 2026.05.12 bbf461bf  SS