Core: prevent warning "Empty filename passed to function" from file load dialog
See https://bugreports.qt.io/browse/QTBUG-67866. First guess: problem may come from OpenFileProxyModel class.
Edited by Wuttke, Joachim
See https://bugreports.qt.io/browse/QTBUG-67866. First guess: problem may come from OpenFileProxyModel class.