Problematic tests list (81 rows):
bugs.core_0995_test  select with FIRST and LEFT JOIN needs excess SORT in plan
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_3610_test  Can insert DUPLICATE keys in UNIQUE index
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_4798_test  Regression: MIN/MAX with a join ignores possible index navigation
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_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.core_5659_test  Bad PLAN generated for query on Firebird v3.0
bugs.core_5756_test  Regression: FB crashes when trying to recreate table that is in use by DML (3.0.3; 3.0.4; 4.0.0)
bugs.core_5843_test  Wrong handling of failures of TRANSACTION START trigger
bugs.core_5908_test  Enhance dynamic libraries loading related error messages
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_5990_test  Pool of external connections
bugs.core_6095_test  Extend trace record for COMMIT/ROLLBACK RETAINING to allow chaining of transaction ids
bugs.core_6252_test  UNIQUE / PRIMARY KEY constraint can be violated when AUTODDL = OFF and mixing commands for DDL and DML
bugs.core_6300_test  Next attachment id, next statement id and some other additions [CORE-6300]
bugs.core_6336_test  Regression in FB 4.x: error "Implementation of text subtype <NNNN> not located" on attempt to use some collations defined in fbintl.conf [CORE6336]
bugs.core_6444_test  Ability to query Firebird configuration using SQL
bugs.core_6469_test  Provide ability to see in the trace log actions related to session management (e.g. ALTER SESSION RESET)
bugs.gh_6282_test  Add DPB properties for time zone bind and decfloat configuration [CORE6032]
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_7062_test  Creation of expression index does not release its statement correctly
bugs.gh_7220_test  Dependencies of subroutines are not preserved after backup restore
bugs.gh_7269_test  Database restore must make every effort on activating deferred indexes
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_8061_addi_test  UNNEST subqueries invalidation. Examples when unnesting can NOT be used.
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_8434_test  Fix implicitly used collations after ALTER DOMAIN
bugs.gh_8488_test  MIN/MAX aggregates may badly affect the join order in queries with mixed INNER/LEFT joins
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_06  Let ISQL show per-table run-time statistics.
functional.blob.test_read_blob_in_multiple_cursors  Ability to read same blob_id using multiple cursors
functional.blob.test_small_blob_caching  Operations with inline streamed blobs when boundary values are used for seek() and read() methods.
functional.gtcs.test_computed_fields_13  Computed fields
functional.index.create.test_all_cases_basic  CREATE INDEX: check all cases
functional.monitoring.test_04  SYSDBA must see all attachments and their transactions, non-privileged user - only those which was of his login.
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:
6.0.0.1819 2026.03.12 61354aef  SS