help dev or fix window association in QPA

can you please either help Rémi Denis-Courmont or fix QT? Remi is https://wiki.videolan.org/User:Courmisch/, who wrote most of the X11 support of VLC video player, and says here: https://trac.videolan.org/vlc/ticket/17910#comment:4:

The last time I checked the Qt5 documentation and headers, there were simply no ways for VLC to embed the video inside the GUI on Wayland. In particular, the window identifier is completely useless with the Wayland QPA (it is just a locally incremented counter). VLC needs to a pair of pointers to the Wayland display server connection, and the surface.

Feel free to reopen this bug if/when Qt is fixed. But in the mean time, separate windows is actually the expected behaviour.