WHERE filter is ignored by DISTINCT IFNULL(GROUP_CONCAT(X), Y) with GROUP BY + ORDER BY

Run the attached sql and you will find a query that returns rows that where explicitly filtered.

… WHERE group = 2 …

group	values

1	A

2	B

3	1

The issue relates to versions, including 10.2.[5-18] 10.3 10.4 but not 10.0.[26-38], 10.1 and 5.5 (tested with the latest docker releases). It does not appear in all mysql versions (5.5, 5.6, 5.7) but mysql_5.7 returns the following error:

ERROR 1055 (42000) at line 28: Expression #1 of ORDER BY clause is not in GROUP BY clause and contains nonaggregated column 'test.bug.name' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

(line 28 is the beginning of the SELECT stmt.