Problematic tests list (44 rows):
bugs.core_2284_test  Records left in RDB$PAGES after rollback of CREATE TABLE statement
bugs.core_4302_addi_test  Lookup (or scan) in descending index could be very inefficient for some keys
bugs.core_4302_test  Lookup (or scan) in descending index could be very inefficient for some keys
bugs.core_4731_test  Prohibit an ability to issue DML or DDL statements on RDB$ tables (CORE-4731)
bugs.core_4754_test  Bugcheck 167 (invalid SEND request) while working with GTT from several attachments (using EXECUTE STATEMENT ... ON EXTERNAL and different roles)
bugs.core_4880_test  Better performance of creating packages containing many functions
bugs.core_5393_test  Bad optimization of some operations with views containing subqueries
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_5501_test  Unclear gstat's diagnostic when damaged page in DB file appears encrypted
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_6414_test  Error message "expected length N, actual M" contains wrong value of M when charset UTF8 is used in the field declaration of a table
bugs.gh_0310_test  System table with keywords
bugs.gh_3810_test  Wrong or missing IS NULL optimization (regression) [CORE3449]
bugs.gh_6785_test  Problem when restoring the database on FB 4.0 RC1 (gbak regression)
bugs.gh_6875_test  Significant performance regression of SIMILAR TO and SUBSTRING(SIMILAR) when pattern is taken from variable (rather than directly specified)
bugs.gh_7050_test  Add table MON$COMPILED_STATEMENTS and columns
bugs.gh_7304_test  Events in system attachments (like garbage collector) are not traced
bugs.gh_7398_test  Worst plan sort created to execute an indexed tables
bugs.gh_7466_plans_tracking_test  Add COMPILE trace events - ability to see execution plan of every PSQL statement.
bugs.gh_7466_test  Add COMPILE trace events for procedures/functions/triggers
bugs.gh_7804_test  The partial index is not involved when filtering conditions through OR.
bugs.gh_7904_test  More realistic cardinality adjustments for unmatchable booleans // FB5 bad plan for query
bugs.gh_8077_test  Error "Too many recursion levels" does not stop execuition of code that uses ON DISCONNECT trigger (FB 4.x+)
bugs.gh_8161_test  Cardinality estimation should use primary record versions only
bugs.gh_8219_test  Database creation in 3.0.12, 4.0.5 and 5.0.1 slower than in previous releases
bugs.gh_8278_test  Avoid index lookup for a NULL key if the condition is known to always be FALSE in this case
bugs.gh_8663_test  Problem with restore time when DB has many indices (possible regression in 6.x)
bugs.gh_8851_test  'Internal error' when calling outer procedure after deleting unused result variable from inner procedure
bugs.gh_9131_test  Improve database creation performance (commit 8bffdd86adae21f07e250dd88a085093f1d5534f)
bugs.gh_9160_test  Failed COMMIT of a DDL transaction leaves orphan RDB$FORMATS records causing subsequent "bugcheck 179 Record N is wrong length" for new tables
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.dtt.test_dtt_max_count  DECLARED TEMPORARY TABLE - check max limit for DTT that can be created within each kind of PSQL unit.
functional.gtcs.test_computed_fields_14  Computed fields
functional.ltt.test_ltt_savepoints_2  LTT. Regression with SAVEPOINTS.
functional.metacache.test_8b4893b3  Shared metacache. DROP <UNIQ_CONSTR> while concurrent Tx involving appropriate index; verify RDB$ content for such intermediate state.
functional.package.temp_tables_multiple_indices_test  Temporary tables in packages (#8974) - multiple indices
functional.table.alter.test_05  ALTER TABLE - ALTER - TO
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
functional.util.gbak_fast_path.test_fp05_scope_and_api  gbak FAST_PATH: eligibility scope, metadata-only mode and fbsvcmgr Services API

This list is the same for:
6.0.0.2401 2026.10.17 454db121  SS