In Motif style QTabWidget exhibits some strange display choices depending on the TabPosition of the tab widget.

The following app demonstrates it:

#include <QApplication>
#include <QVBoxLayout>
#include <QMainWindow>
#include <QWidget>
#include <QTabWidget>
#include <QTextEdit>
#include <QMotifStyle>
#include <QComboBox>

class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = 0)
: QMainWindow(parent)
{
setCentralWidget(new QWidget(this));
QVBoxLayout *lay = new QVBoxLayout(centralWidget());

for (int i=0; i<=QTabWidget::East; ++i) {
QTabWidget *tw = new QTabWidget(centralWidget());
tw->setTabPosition((QTabWidget::TabPosition)i);
for (int i=0; i<2; ++i)

{ QWidget *w = new QWidget(tw); QVBoxLayout *l = new QVBoxLayout(w); l->addItem(new QSpacerItem(1, 1)); QComboBox *box = new QComboBox(w); box->addItem("foo"); l->addWidget(box); l->addItem(new QSpacerItem(1, 1)); tw->addTab(w, "Tab number " + QString::number(i + 1)); }

lay->addWidget(tw);
}
}
public slots:
};

#include "main.moc"

int main(int argc, char **argv)
{
QApplication a(argc, argv);
a.setStyle(new QMotifStyle);
MainWindow w;
w.show();
return a.exec();
}

Notice the line painted above/left of the current tab of the South/East tabs. This isn't consistent and also makes it harder to see which tab is current