Yes, you have to check if "revisions history" are enabled. ;) 
https://github.com/phpbb/phpbb/pull/1200/files#diff-16b9e8e968b498dd3c4c726b6d831a85R1677
https://github.com/phpbb/phpbb/pull/1200/files#diff-7400ab768eaa5b263109a3bbbdfae531R218