Source: https://codereview.qt-project.org/c/qt/qtbase/+/267242
Upstream: yes
Reason: fix focus stealing in applications (e.g. VirtualBox)

--- qtbase/src/plugins/platforms/xcb/qxcbconnection.cpp	2019-06-13 06:18:18.000000000 +0200
+++ qtbase/src/plugins/platforms/xcb/qxcbconnection.cpp	2019-07-21 11:56:22.250127747 +0200
@@ -133,6 +133,7 @@
         qunsetenv("DESKTOP_STARTUP_ID");
 
     m_focusInTimer.setSingleShot(true);
+    m_focusInTimer.setInterval(100);
     m_focusInTimer.callOnTimeout([]() {
         // No FocusIn events for us, proceed with FocusOut normally.
         QWindowSystemInterface::handleWindowActivated(nullptr, Qt::ActiveWindowFocusReason);
--- qtbase/src/plugins/platforms/xcb/qxcbwindow.cpp	2019-06-13 06:18:18.000000000 +0200
+++ qtbase/src/plugins/platforms/xcb/qxcbwindow.cpp	2019-07-21 11:58:00.255122346 +0200
@@ -848,7 +848,7 @@
     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 {