I noticed a weird behavior when running a frameless widget in PyQt.
If I minimize it in taskbar multiple times, a Windows XP title bar appears in the top left corner during a few milliseconds and then disappears.
Here is a simple code to reproduce the problem :
from PyQt5 import QtCore, QtWidgets
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
ui = QtWidgets.QWidget()
ui.setWindowFlags(ui.windowFlags() | QtCore.Qt.FramelessWindowHint)
I reported the issue to Qt and it seems to be a general Windows bug :
Sergio Martins added a comment
I can reproduce this problem with a pure Windows example, (passing WS_VISIBLE | WS_POPUP | WS_SYSMENU | WS_MINIMIZEBOX to CreateWindowEx()). Doesn't seem fixable, other than removing the minimize button capability.