Determine whether the file chooser associated to this #WebKitFileChooserRequest should allow selecting multiple files, which depends on the HTML input element having a 'multiple' attribute defined.
%TRUE if the file chooser should allow selecting multiple files or %FALSE otherwise.
See Implementation
Determine whether the file chooser associated to this #WebKitFileChooserRequest should allow selecting multiple files, which depends on the HTML input element having a 'multiple' attribute defined.