diff --git a/src/widgets/widgets/qtabwidget.cpp b/src/widgets/widgets/qtabwidget.cpp
index 6ca1f21886e..b7e253dedc9 100644
--- a/src/widgets/widgets/qtabwidget.cpp
+++ b/src/widgets/widgets/qtabwidget.cpp
@@ -1361,7 +1361,8 @@ void QTabWidget::setUsesScrollButtons(bool useButtons)
 bool QTabWidget::documentMode() const
 {
     Q_D(const QTabWidget);
-    return d->tabs->documentMode();
+    // QStyleSheetStyle could query documentMode during creation of our QTabBar.
+    return d->tabs ? d->tabs->documentMode() : false;
 }
 
 void QTabWidget::setDocumentMode(bool enabled)
diff --git a/tests/auto/widgets/styles/qstylesheetstyle/tst_qstylesheetstyle.cpp b/tests/auto/widgets/styles/qstylesheetstyle/tst_qstylesheetstyle.cpp
index a1bbf14bd61..2ccf7ccdc27 100644
--- a/tests/auto/widgets/styles/qstylesheetstyle/tst_qstylesheetstyle.cpp
+++ b/tests/auto/widgets/styles/qstylesheetstyle/tst_qstylesheetstyle.cpp
@@ -20,6 +20,8 @@
 #include <QtWidgets/QSplitter>
 #include <QtWidgets/QStyle>
 #include <QtWidgets/QStyleFactory>
+#include <QtWidgets/QTabBar>
+#include <QtWidgets/QTabWidget>
 #include <QtWidgets/QTableWidget>
 #include <QtWidgets/QToolButton>
 #include <QtWidgets/QToolTip>
@@ -115,6 +117,7 @@ private slots:
     void appStyle();
     void QTBUG11658_cachecrash();
     void styleSheetTargetAttribute();
+    void tabWidgetDocumentModeCrash();
     void unpolish();
 
     void highdpiImages_data();
@@ -2331,6 +2334,16 @@ void tst_QStyleSheetStyle::styleSheetTargetAttribute()
     QCOMPARE(pb.testAttribute(Qt::WA_StyleSheetTarget), false);
 }
 
+void tst_QStyleSheetStyle::tabWidgetDocumentModeCrash()
+{
+    // Don't crash when matching accessing documentMode of QTabWidget while styling QTabBar.
+    qApp->setStyleSheet("QTabWidget[documentMode=true] QTabBar { font-size: 40pt; }");
+
+    QTabWidget tabWidget;
+    tabWidget.setDocumentMode(true);
+    QCOMPARE(FONTSIZE(*tabWidget.tabBar()), 40);
+}
+
 void tst_QStyleSheetStyle::unpolish()
 {
     QWidget w;