Problematic tests list (26 rows):
bugs.core_3690_dialect_3_test  Wrong warning message for ambiguous query
bugs.core_5275_test  Expression index may become inconsistent if CREATE INDEX was interrupted after b-tree creation but before commiting
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_5618_test  Part of the pages of the second level blobs is not released when deleting relations
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.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_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_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
functional.arno.optimizer.test_opt_inner_join_05  INNER JOIN join order LIKE and STARTING WITH
functional.gtcs.test_returning_01  Test of RETURNING clause: INSERT, UPDATE, MERGE.
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

This list is the same for:
6.0.0.2033 2026.06.25 3427fbc3  SS