[4.4.0] QFileDialog closes when regexp is inserted in the line edit

The behavior should be applying the filter (e.g.: "*.jpg") to the current directory (like the Qt3 file dialog does), and not close the dialog. Altough the Qt3 dialog adds a new filter entry to the filters combo box (without even emitting the filtersChanged() signal). This behavior is also not wished, since it replaces the selected filter.