remove print-view as well, re #993

resources/assets/javascripts/bootstrap/qr_code.js

@@ -16,6 +16,7 @@ STUDIP.ready((event) => {
 
     $(document).on('fullscreenchange webkitfullscreenchange mozfullscreenchange MSFullscreenChange', () => {
         // After the print action is called we must reset the style changes made above:
+        $('#qr_code').removeClass('print-view');
         $('#layout_wrapper.print-qrcode').removeClass('print-qrcode').show();
     });
 });