A working example of a workaround the issue by compiling the ui files with pyuic5, here in a ui_testui.py file. ```python from PyQt5 import QtWidgets from .ui_testui import Ui_TestUi class TestUi(QtWidgets.Qwidget): def __init__(self, parent=None): super(TestUi, self).__init__(parent) self.ui = Ui_TestUi() self.ui.setupUi(self) ``` It would be best to contact riverbankcomputing, I believe. -- You are receiving this because you commented. Reply to this email directly or view it on GitHub: https://github.com/tohojo/flent/issues/167#issuecomment-515734468