1 files changed, 16 insertions, 4 deletions
diff --git a/src/widgets/widgets/qsizegrip.cpp b/src/widgets/widgets/qsizegrip.cpp
index 835af9c7b8..95a4beeb57 100644
--- a/src/widgets/widgets/qsizegrip.cpp
+++ b/src/widgets/widgets/qsizegrip.cpp
@@ -128,7 +128,7 @@ QSizeGripPrivate::QSizeGripPrivate()
     : dxMax(0)
     , dyMax(0)
     , gotMousePress(false)
-    , tlw(0)
+    , tlw(nullptr)
     , m_platformSizeGrip(false)
 {
 }
@@ -195,7 +195,7 @@ Qt::Corner QSizeGripPrivate::corner() const
     parent.
 */
 QSizeGrip::QSizeGrip(QWidget * parent)
-    : QWidget(*new QSizeGripPrivate, parent, 0)
+    : QWidget(*new QSizeGripPrivate, parent, { })
 {
     Q_D(QSizeGrip);
     d->init();
@@ -260,6 +260,17 @@ void QSizeGrip::paintEvent(QPaintEvent *event)
     parameter.
 */
 
+static Qt::Edges edgesFromCorner(Qt::Corner corner)
+{
+    switch (corner) {
+    case Qt::TopLeftCorner: return Qt::TopEdge | Qt::LeftEdge;
+    case Qt::TopRightCorner: return Qt::TopEdge | Qt::RightEdge;
+    case Qt::BottomLeftCorner: return Qt::BottomEdge | Qt::LeftEdge;
+    case Qt::BottomRightCorner: return Qt::BottomEdge | Qt::RightEdge;
+    }
+    return Qt::Edges{};
+}
+
 void QSizeGrip::mousePressEvent(QMouseEvent * e)
 {
     if (e->button() != Qt::LeftButton) {
@@ -281,8 +292,9 @@ void QSizeGrip::mousePressEvent(QMouseEvent * e)
         && !tlw->testAttribute(Qt::WA_DontShowOnScreen)
         && !tlw->hasHeightForWidth()) {
         QPlatformWindow *platformWindow = tlw->windowHandle()->handle();
-        const QPoint topLevelPos = mapTo(tlw, e->pos());
-        d->m_platformSizeGrip = platformWindow && platformWindow->startSystemResize(topLevelPos, d->m_corner);
+        const Qt::Edges edges = edgesFromCorner(d->m_corner);
+        if (!QGuiApplication::platformName().contains(QStringLiteral("xcb"))) // ### FIXME QTBUG-69716
+            d->m_platformSizeGrip = platformWindow && platformWindow->startSystemResize(edges);
     }
 
     if (d->m_platformSizeGrip)