Simple qml red rectangle displays with strange transparent layout

I update from qt 5.12.3 to 5.14.2

I met strange issue, the content of rectangle cannot be shown.

Here is my qml file. (simple)

#test.qml, draw a red rectangle

import QtQuick 2.0

Rectangle {
width: 500
height: 500
color: "red"
}

When I run this qml,  it only shows the boder, the content is transparent, like below picture.

I tried 3 scenarioes.

1. qmlsene test.qml             # the content is transparent
2. qmlsene test.qml --transparent      # the red content can be show
3. qmlsene test.qml --fullscreen         # the red content can be show

Scenraio 1 and 2 has no log output.

3 has the following output.

root@euto-v9:~# qmlscene test.qml --fullscreen
qt.qpa.wayland: Wayland does not support QWindow::requestActivate()

Do you have any idea for this issue? or do you have some tracing tools to find the cause of this issue? Sorry that I cannot attach a picture because of security policy.

Thank you very much!