from PySide6.QtCore import Qt
from PySide6.QtWidgets import QApplication, QDockWidget, QLabel, QMainWindow, QPushButton

class MainWindow (QMainWindow):
	
	def __init__ (self):
		super().__init__()
		btn = QPushButton('Create Dock')
		btn.clicked.connect(self.evt_clicked)
		self.setCentralWidget(btn)

	def evt_clicked (self) -> None:
		dock = QDockWidget('Dock', self)
		dock.setWidget(QLabel('Label'))
		self.addDockWidget(Qt.BottomDockWidgetArea, dock)

if __name__ == '__main__':
	app = QApplication()
	window = MainWindow()
	window.show()
	app.exec()

I clicked the button a few times to create a few docked widgets, then dragged one out of the QMainWindow area and onto my desktop to float it. After I did this, NONE of the QMainWindow's contents, the button and all remaining docks included, will resize when I resize the window itself. Taking any floating dock and re-attaching it to the window fixes this problem.

I made a short video that showcases the problem: https://youtu.be/Gfpu0l4zN5M

Does anyone else know how to fix this?