3 files changed, 10 insertions, 3 deletions
diff --git a/src/plugins/platforms/xcb/qxcbconnection.cpp b/src/plugins/platforms/xcb/qxcbconnection.cpp
index d27a288feb..cac6345b66 100644
--- a/src/plugins/platforms/xcb/qxcbconnection.cpp
+++ b/src/plugins/platforms/xcb/qxcbconnection.cpp
@@ -132,7 +132,9 @@ QXcbConnection::QXcbConnection(QXcbNativeInterface *nativeInterface, bool canGra
     if (!m_startupId.isNull())
         qunsetenv("DESKTOP_STARTUP_ID");
 
+    const int focusInDelay = 100;
     m_focusInTimer.setSingleShot(true);
+    m_focusInTimer.setInterval(focusInDelay);
     m_focusInTimer.callOnTimeout([]() {
         // No FocusIn events for us, proceed with FocusOut normally.
         QWindowSystemInterface::handleWindowActivated(nullptr, Qt::ActiveWindowFocusReason);
diff --git a/src/plugins/platforms/xcb/qxcbeventqueue.cpp b/src/plugins/platforms/xcb/qxcbeventqueue.cpp
index 82a36c0727..759ee3cc95 100644
--- a/src/plugins/platforms/xcb/qxcbeventqueue.cpp
+++ b/src/plugins/platforms/xcb/qxcbeventqueue.cpp
@@ -226,11 +226,13 @@ void QXcbEventQueue::run()
     };
 
     while (!m_closeConnectionDetected && (event = xcb_wait_for_event(connection))) {
+        m_newEventsMutex.lock();
         enqueueEvent(event);
         while (!m_closeConnectionDetected && (event = xcb_poll_for_queued_event(connection)))
             enqueueEvent(event);
 
         m_newEventsCondition.wakeOne();
+        m_newEventsMutex.unlock();
         wakeUpDispatcher();
     }
 
@@ -350,9 +352,12 @@ bool QXcbEventQueue::peekEventQueue(PeekerCallback peeker, void *peekerData,
 
 void QXcbEventQueue::waitForNewEvents(unsigned long time)
 {
-    m_newEventsMutex.lock();
+    QMutexLocker locker(&m_newEventsMutex);
+    QXcbEventNode *tailBeforeFlush = m_flushedTail;
+    flushBufferedEvents();
+    if (tailBeforeFlush != m_flushedTail)
+        return;
     m_newEventsCondition.wait(&m_newEventsMutex, time);
-    m_newEventsMutex.unlock();
 }
 
 void QXcbEventQueue::sendCloseConnectionEvent() const
diff --git a/src/plugins/platforms/xcb/qxcbwindow.cpp b/src/plugins/platforms/xcb/qxcbwindow.cpp
index 396b47001d..1d1a4eea1c 100644
--- a/src/plugins/platforms/xcb/qxcbwindow.cpp
+++ b/src/plugins/platforms/xcb/qxcbwindow.cpp
@@ -848,7 +848,7 @@ void QXcbWindow::doFocusOut()
     connection()->setFocusWindow(nullptr);
     relayFocusToModalWindow();
     // Do not set the active window to nullptr if there is a FocusIn coming.
-    connection()->focusInTimer().start(400);
+    connection()->focusInTimer().start();
 }
 
 struct QtMotifWmHints {