Qt5.11.1: DirectFb block generic plugin

[debian]

Hello!
I cross-compile Qt-5.11.1 for Broadcom mips SoC with DirectFb support, application success start, output to screen present and application get commands from IR.
But I have custom generic plugin, I use QT_QPA_GENERIC_PLUGINS environment for load it, plugin success load and get commands from user, but application not get commands from it.

Register generic plugin

QInputDeviceManagerPrivate::get(
    QGuiApplicationPrivate::inputDeviceManager())->setDeviceCount(
        QInputDeviceManager::DeviceTypeKeyboard, 1);

Send event from plugin

struct KeyStatus {
    quint32 code;
    bool press;
    bool repeat;
};
KeyStatus status = ...;
QWindowSystemInterface::handleKeyEvent(0,
    status.press ? QEvent::KeyPress : QEvent::KeyRelease,
    status.code,
    0,
    QString(),
    status.repeat); 

Why application not get commands from custom plugin if it use DirectFb? I also use with plugin if application use LinuxFb and in this case problem not present.
DirectFb plugin can block/disable commands from other generic plugins?

Thank you and excuse me my bad English.

[debian]

$ git diff
diff --git a/src/plugins/platforms/directfb/qdirectfbinput.cpp b/src/plugins/platforms/directfb/qdirectfbinput.cpp
index 025edb28b5..33d6328aef 100644
--- a/src/plugins/platforms/directfb/qdirectfbinput.cpp
+++ b/src/plugins/platforms/directfb/qdirectfbinput.cpp
@@ -188,7 +188,7 @@ void QDirectFbInput::handleKeyEvents(const DFBEvent &event)
     if (DFB_KEY_TYPE(event.window.key_symbol) == DIKT_UNICODE)
         character = QChar(event.window.key_symbol);
     QWindow *tlw = m_tlwMap.value(event.window.window_id);
-    QWindowSystemInterface::handleKeyEvent(tlw, timestamp, type, key, modifiers, character);
+    QWindowSystemInterface::handleKeyEvent(/*tlw*/nullptr, timestamp, type, key, modifiers, character);
 }
 
 void QDirectFbInput::handleEnterLeaveEvents(const DFBEvent &event)

With this changes app also not get keyboard event from directfb plugin.