Crash when creating new C++ class (Wayland protocol error)

When creating new C++ class and starting typing the name of a custom base class (e.g. "QS" for QStyledItemDelegate), Qt Creator crashes with following error:

xdg_surface#64: error 2: the surface already has a role assigned xdg_popup
The Wayland connection experienced a fatal error: Protocol error

openSUSE Tumblweed
KDE Plasma Wayland 6.3.4
Qt 6.9.0
Qt Creator 16.0.1 from openSUSE repos

I attached output of running Qt Creator with WAYLAND_DEBUG=1 environment variable, from the moment of opening dialog for creation of C++ file.

With official Qt Creator 16.0.1 build (which uses Qt 6.8.3 BTW) the crash is not reproducible, but the autocompletion popup for base class text field is displayed in the center of the screen with its own window decorations.