This is the revision history for fold case in <libera.chat:#esolangs>

factoid_idsubjectcopulapredicateauthornamespace
10258 fold case is for case-insensitive comparison, try perldoc -f fc (5.16+), see http://www.effectiveperlprogramming.com/2012/02/fold-cases-properly/ tm604 <*:##NULL>