PySide6中为QScrollArea添加QGraphicsOpacityEffect的效果后出现阴影和拖影

[Moonsea]

这里是简化后的代码：

from sys import argv

from PySide6.QtCore import QTimer
from PySide6.QtWidgets import QLabel, QScrollArea, QGraphicsOpacityEffect, QApplication, QMainWindow


class Test(QMainWindow):
    timer = QTimer()

    def __init__(self, parent=None, *args, **kwargs):
        super().__init__(parent, *args, **kwargs)

        self.parent = parent

        label = QLabel('test\n'*20)
        label.setStyleSheet('font-size:20px;')

        scroll_area = QScrollArea()
        scroll_area.setWidget(label)
        self.setCentralWidget(scroll_area)

        opacity = QGraphicsOpacityEffect(scroll_area)
        opacity.setOpacity(0.5)
        scroll_area.setGraphicsEffect(opacity)

        self.show()


if __name__ == '__main__':
    app = QApplication(argv)
    ex = Test()
    exit(app.exec())

用的是python3.9.13 pyside6 6.5.0
别的控件都是正常的，只有QScrollArea出问题
请问怎么解决呢？