diff --git a/src/widgets/dialogs/qfiledialog.cpp b/src/widgets/dialogs/qfiledialog.cpp
index ae8d0c137ab..966d86b0890 100644
--- a/src/widgets/dialogs/qfiledialog.cpp
+++ b/src/widgets/dialogs/qfiledialog.cpp
@@ -418,6 +418,7 @@ QByteArray QFileDialog::saveState() const
     int version = 4;
     QByteArray data;
     QDataStream stream(&data, QIODevice::WriteOnly);
+    stream.setVersion(QDataStream::Qt_5_0);
 
     stream << qint32(QFileDialogMagic);
     stream << qint32(version);
@@ -452,6 +453,7 @@ bool QFileDialog::restoreState(const QByteArray &state)
     Q_D(QFileDialog);
     QByteArray sd = state;
     QDataStream stream(&sd, QIODevice::ReadOnly);
+    stream.setVersion(QDataStream::Qt_5_0);
     if (stream.atEnd())
         return false;
     QStringList history;
diff --git a/src/widgets/itemviews/qheaderview.cpp b/src/widgets/itemviews/qheaderview.cpp
index a081a7d0f95..413857bf6c1 100644
--- a/src/widgets/itemviews/qheaderview.cpp
+++ b/src/widgets/itemviews/qheaderview.cpp
@@ -1742,6 +1742,7 @@ QByteArray QHeaderView::saveState() const
     Q_D(const QHeaderView);
     QByteArray data;
     QDataStream stream(&data, QIODevice::WriteOnly);
+    stream.setVersion(QDataStream::Qt_5_0);
     stream << QHeaderViewPrivate::VersionMarker;
     stream << 0; // current version is 0
     d->write(stream);
@@ -1763,6 +1764,7 @@ bool QHeaderView::restoreState(const QByteArray &state)
         return false;
     QByteArray data = state;
     QDataStream stream(&data, QIODevice::ReadOnly);
+    stream.setVersion(QDataStream::Qt_5_0);
     int marker;
     int ver;
     stream >> marker;
diff --git a/src/widgets/widgets/qmainwindow.cpp b/src/widgets/widgets/qmainwindow.cpp
index 88f710870bc..73ca584c7fe 100644
--- a/src/widgets/widgets/qmainwindow.cpp
+++ b/src/widgets/widgets/qmainwindow.cpp
@@ -1217,6 +1217,7 @@ QByteArray QMainWindow::saveState(int version) const
 {
     QByteArray data;
     QDataStream stream(&data, QIODevice::WriteOnly);
+    stream.setVersion(QDataStream::Qt_5_0);
     stream << QMainWindowLayout::VersionMarker;
     stream << version;
     d_func()->layout->saveState(stream);
@@ -1245,6 +1246,7 @@ bool QMainWindow::restoreState(const QByteArray &state, int version)
         return false;
     QByteArray sd = state;
     QDataStream stream(&sd, QIODevice::ReadOnly);
+    stream.setVersion(QDataStream::Qt_5_0);
     int marker, v;
     stream >> marker;
     stream >> v;
diff --git a/src/widgets/widgets/qmainwindowlayout.cpp b/src/widgets/widgets/qmainwindowlayout.cpp
index d1ea0b57da0..4a199e0b18d 100644
--- a/src/widgets/widgets/qmainwindowlayout.cpp
+++ b/src/widgets/widgets/qmainwindowlayout.cpp
@@ -1164,10 +1164,12 @@ bool QMainWindowLayoutState::restoreState(QDataStream &_stream,
     }
 
     QDataStream ds(copy);
+    ds.setVersion(_stream.version());
     if (!checkFormat(ds))
         return false;
 
     QDataStream stream(copy);
+    stream.setVersion(_stream.version());
 
     while (!stream.atEnd()) {
         uchar marker;
diff --git a/src/widgets/widgets/qsplitter.cpp b/src/widgets/widgets/qsplitter.cpp
index 8507ebf3564..7dfc2a04fa2 100644
--- a/src/widgets/widgets/qsplitter.cpp
+++ b/src/widgets/widgets/qsplitter.cpp
@@ -1650,6 +1650,7 @@ QByteArray QSplitter::saveState() const
     int version = 1;
     QByteArray data;
     QDataStream stream(&data, QIODevice::WriteOnly);
+    stream.setVersion(QDataStream::Qt_5_0);
 
     stream << qint32(SplitterMagic);
     stream << qint32(version);
@@ -1691,6 +1692,7 @@ bool QSplitter::restoreState(const QByteArray &state)
     int version = 1;
     QByteArray sd = state;
     QDataStream stream(&sd, QIODevice::ReadOnly);
+    stream.setVersion(QDataStream::Qt_5_0);
     QList<int> list;
     bool b;
     qint32 i;
diff --git a/tests/auto/widgets/itemviews/qheaderview/tst_qheaderview.cpp b/tests/auto/widgets/itemviews/qheaderview/tst_qheaderview.cpp
index 5e67029cf53..93f991b0fe3 100644
--- a/tests/auto/widgets/itemviews/qheaderview/tst_qheaderview.cpp
+++ b/tests/auto/widgets/itemviews/qheaderview/tst_qheaderview.cpp
@@ -146,6 +146,7 @@ private slots:
     void moveSectionAndReset();
     void moveSectionAndRemove();
     void saveRestore();
+    void QTBUG99487_saveRestoreQt5Compat();
     void restoreToMoreColumns();
     void restoreToMoreColumnsNoMovedColumns();
     void restoreBeforeSetModel();
@@ -1716,16 +1717,24 @@ static QByteArray savedState()
     return h1.saveState();
 }
 
-void tst_QHeaderView::saveRestore()
+// As generated by savedState()
+static const QByteArray qt5SavedSate = QByteArrayLiteral("\x00\x00\x00\xFF\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x02\x01\x00\x00\x00\x04\x00\x00\x00\x02\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x04\x00\x00\x00\x02\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x04\b\x00\x00\x00\x01\x00\x00\x00\x03\x00\x00\x00""d\x00\x00\x00\xD2\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00""d\x00\x00\x00\x00\x00\x00\x00\x84\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00""d\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\n\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00""d\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x03\xE8\x00\x00\x00\x00\x00\x00\x00\x00\x00");
+
+enum class SaveRestoreOption
+{
+    CheckGeneratedState,
+    DoNotCheckGeneratedState,
+};
+
+static void saveRestoreImpl(const QByteArray &state, SaveRestoreOption option)
 {
     QStandardItemModel m(4, 4);
-    const QByteArray s1 = savedState();
 
     QHeaderView h2(Qt::Vertical);
     QSignalSpy spy(&h2, &QHeaderView::sortIndicatorChanged);
 
     h2.setModel(&m);
-    QVERIFY(h2.restoreState(s1));
+    QVERIFY(h2.restoreState(state));
 
     QCOMPARE(spy.count(), 1);
     QCOMPARE(spy.at(0).at(0).toInt(), 2);
@@ -1740,12 +1749,30 @@ void tst_QHeaderView::saveRestore()
     QVERIFY(h2.isSectionHidden(3));
     QCOMPARE(h2.hiddenSectionCount(), 1);
 
-    QByteArray s2 = h2.saveState();
-    QCOMPARE(s1, s2);
+    switch (option) {
+    case SaveRestoreOption::CheckGeneratedState:
+    {
+        QByteArray s2 = h2.saveState();
+        QCOMPARE(state, s2);
+        break;
+    }
+    case SaveRestoreOption::DoNotCheckGeneratedState:
+        break;
+    };
 
     QVERIFY(!h2.restoreState(QByteArrayLiteral("Garbage")));
 }
 
+void tst_QHeaderView::saveRestore()
+{
+    saveRestoreImpl(savedState(), SaveRestoreOption::CheckGeneratedState);
+}
+
+void tst_QHeaderView::QTBUG99487_saveRestoreQt5Compat()
+{
+    saveRestoreImpl(qt5SavedSate, SaveRestoreOption::DoNotCheckGeneratedState);
+}
+
 void tst_QHeaderView::restoreToMoreColumns()
 {
     // Restore state onto a model with more columns