Using a stylus to open a QMenu in a window before interacting with it using a mouse or touchpad causes the menu to open as a standalone window

STEPS TO REPRODUCE

1. Launch KDE's Dolphin file manager, either using a stylus to click its Task Manager launcher button, or even just opening it in a terminal window by running `dolphin`
2. Use the stylus to open a menu in some way: click the hamburger menu button in the toolbar or the dropdown menu button for sort ordering. If the in-window menubar was visible, clicking on one of the menus reproduces it too

ACTUAL RESULT

The QMenu for the requested menu opens, but as a standalone window, not a drop-down menu. This is 100% reproducible for me with the above steps.

EXPECTED RESULT

The QMenu for the requested menu opens as a drop-down menu

ADDITIONAL INFORMATION

After step 1, if I use a mouse or touchpad to click on anything inside the window (excluding the window decoration), the problem does not occur in step 3.

WAYLAND_DEBUG=1 log attached.