Hello,
I just installed mantisbt 1.2.12 and if I clik on "Summary" link I retrieve this error:

APPLICATION ERROR 0000401
Database query failed. Error received from database was #-1: ERROR: column "b.category_id" must appear in the GROUP BY clause or be used in an aggregate function
LINE 1: ...OUNT(b.id) as bugcount, c.name AS category_name, category_i...
^ for the query: SELECT COUNT(b.id) as bugcount, c.name AS category_name, category_id, b.status
FROM mantis_bug_table b
JOIN mantis_category_table AS c ON b.category_id=c.id
WHERE b.project_id IN (2,1)
GROUP BY c.name, b.status
ORDER BY c.name.

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