X11: Qt Creator locks up if an application uses clipboard and sits on a breakpoint

#include <QApplication>
#include <QImage>
#include <QClipboard>
int main(int argc, char** argv) {
 QApplication app(argc, argv);
 app.clipboard()->setImage(QImage(32,32,QImage::Format_ARGB32));
 qDebug("breakpoint on this line");
}