Hi all, I upgraded my wiki after full backups from 1.13.1 to the 1.15.0 quaterly release. I tested some of the features and when trying to view the history i get the following error A database query syntax error has occurred. This may indicate a bug in the software. The last attempted database query was:     (SQL query hidden) from within function "ChangeTags::listDefinedTags". MySQL returned error "1146: Table 'idt.mw_valid_tag' doesn't exist (localhost)". When setup to my previous php version with the migrated mySQL DB the history feature works fine. 2 questions: *     Is it safe to put back my WIKi version 1.13.1 running on the migrated DB *     How to fix the issue with the history feature ?