SUMMARY

Menus in lxqt-panel are positioned using an anchor rectangle that is not within the parent geometry. This is not permitted by the protocol:

```
	When the xdg_positioner object is used to position a child surface, the
	anchor rectangle may not extend outside the window geometry of the
	positioned child's parent surface.
```


STEPS TO REPRODUCE
1. Run the lxqt-panel with `WAYLAND_DEBUG=client` 
2. Pull up a menu

OBSERVED RESULT

```
[1782416.373] {Default Queue}  -> wl_compositor#4.create_surface(new id wl_surface#43)
[1782417.605] {Default Queue}  -> wp_fractional_scale_manager_v1#16.get_fractional_scale(new id wp_fractional_scale_v1#47, wl_surface#43)
[1782417.717] {Default Queue}  -> xdg_wm_base#3.get_xdg_surface(new id xdg_surface#42, wl_surface#43)
[1782417.764] {Default Queue}  -> xdg_wm_base#3.create_positioner(new id xdg_positioner#44)
[1782417.852] {Default Queue}  -> xdg_positioner#44.set_anchor_rect(0, -550, 1, 1)
```

This is wrong: `set_anchor_rect(0, -550, 1, 1)`

EXPECTED RESULT

I'd expect the anchor rect to be the position of a widget in the parent window. A position outside the window geometry with a size of 1x1 looks bogus. Other parts of Qt seem to have this the way I expect (e.g. the qterminal menus)

SOFTWARE/OS VERSIONS
Fedora Linux: 42 (LXQt Prerelease)
Qt Version:  6

ADDITIONAL INFORMATION

Previous discussion at https://github.com/lxqt/lxqt-wayland-session/pull/40#issuecomment-2666380287

Testing with ISO from https://koji.fedoraproject.org/koji/buildinfo?buildID=2660492