diff --git a/src/widgets/itemviews/qheaderview.cpp b/src/widgets/itemviews/qheaderview.cpp
index 9ce09dbacc0..614242118ef 100644
--- a/src/widgets/itemviews/qheaderview.cpp
+++ b/src/widgets/itemviews/qheaderview.cpp
@@ -1518,6 +1518,7 @@ void QHeaderView::setDefaultSectionSize(int size)
     Q_D(QHeaderView);
     if (size < 0 || size > maxSizeSection)
         return;
+    d->oldDefaultSectionSize = d->defaultSectionSize;
     d->setDefaultSectionSize(size);
 }
 
@@ -1525,7 +1526,9 @@ void QHeaderView::resetDefaultSectionSize()
 {
     Q_D(QHeaderView);
     if (d->customDefaultSectionSize) {
+        d->oldDefaultSectionSize = d->defaultSectionSize;
         d->updateDefaultSectionSizeFromStyle();
+        d->setDefaultSectionSize(d->defaultSectionSize);
         d->customDefaultSectionSize = false;
     }
 }
@@ -2376,8 +2379,12 @@ bool QHeaderView::event(QEvent *e)
         }
         break; }
     case QEvent::StyleChange:
-        if (!d->customDefaultSectionSize)
+        if (!d->customDefaultSectionSize) {
+            d->oldDefaultSectionSize = d->defaultSectionSize;
             d->updateDefaultSectionSizeFromStyle();
+            d->setDefaultSectionSize(d->defaultSectionSize);
+            d->customDefaultSectionSize = false;
+        }
         break;
     default:
         break;
@@ -3850,7 +3857,11 @@ void QHeaderViewPrivate::setDefaultSectionSize(int size)
     for (int i = 0; i < sectionItems.size(); ++i) {
         QHeaderViewPrivate::SectionItem &section = sectionItems[i];
         if (hiddenSectionSize.isEmpty() || !isVisualIndexHidden(i)) { // resize on not hidden.
-            const int newSize = size;
+            // Resize to the new default if the current size is the old default,
+            // or 0. Otherwise don't change.
+            const int newSize = (section.size == oldDefaultSectionSize || !section.size)
+                              ? size
+                              : section.size;
             if (newSize != section.size) {
                 length += newSize - section.size; //the whole length is changed
                 const int oldSectionSize = section.sectionSize();
diff --git a/src/widgets/itemviews/qheaderview_p.h b/src/widgets/itemviews/qheaderview_p.h
index 8b214e1d03e..e0c601105ee 100644
--- a/src/widgets/itemviews/qheaderview_p.h
+++ b/src/widgets/itemviews/qheaderview_p.h
@@ -272,6 +272,7 @@ public:
     int stretchSections;
     int contentsSections;
     int defaultSectionSize;
+    int oldDefaultSectionSize = -1;
     int minimumSectionSize;
     int maximumSectionSize;
     int lastSectionSize;
diff --git a/tests/auto/widgets/itemviews/qheaderview/tst_qheaderview.cpp b/tests/auto/widgets/itemviews/qheaderview/tst_qheaderview.cpp
index 012fb17ee95..5dd6d35b4c5 100644
--- a/tests/auto/widgets/itemviews/qheaderview/tst_qheaderview.cpp
+++ b/tests/auto/widgets/itemviews/qheaderview/tst_qheaderview.cpp
@@ -3289,6 +3289,10 @@ void tst_QHeaderView::resizeToContentTest()
     QCOMPARE(hh->sectionSize(3), 200);
     hh->setMaximumSectionSize(-1);
 
+    // give all sections a zero-size, so that setDefaultSectionSize resets their size
+    for (int u = 0; u < view->count(); ++u)
+        view->resizeSection(u, 0);
+
     view->setDefaultSectionSize(25); // To make sure our precalced data are correct. We do not know font height etc.
 
     const int precalced_results[] =  { -1523279360, -1523279360, -1347156568, 1, 1719705216, 1719705216, 12500 };
diff --git a/tests/auto/widgets/itemviews/qtableview/tst_qtableview.cpp b/tests/auto/widgets/itemviews/qtableview/tst_qtableview.cpp
index 681be2491dc..6848b28f494 100644
--- a/tests/auto/widgets/itemviews/qtableview/tst_qtableview.cpp
+++ b/tests/auto/widgets/itemviews/qtableview/tst_qtableview.cpp
@@ -4950,7 +4950,6 @@ void tst_QTableView::resetDefaultSectionSize()
     view.verticalHeader()->resetDefaultSectionSize();
     view.show();
     QVERIFY(QTest::qWaitForWindowExposed(&view));
-    QEXPECT_FAIL("", "Reverted fix for QTBUG-116013 due to QTBUG-122109", Continue);
     QCOMPARE(view.verticalHeader()->logicalIndexAt(9, 45), 1);
 }