In Windows, Opera has not had a menu bar since version 15 - and it was optional prior to that.
Opera 12.17 is the latest version to use the old Presto engine - and to have the option of a menu bar. Last year they released a version based on the same engine as Chrome (the engine is currently known as Blink), but since it is a different engine they do not consider it an update to 12.x - it is something new, not an update.