Fix #151 and a crash bug related to sub frameless window

Sine Striker

2024-11-21 c3ef42dad254f6d04cab521c9ae619a46bb84f7a

 examples/mainwindow/mainwindow.qrc

@@ -1,5 +1,6 @@
<RCC>
    <qresource prefix="/">
        <file>dark-style.qss</file>
        <file>light-style.qss</file>
    </qresource>
</RCC>