Dropdowns showing half a screen away from where they were clicked (on linux wayland and ultrawide screen)

[JacekP1]

When hovering over the main dropdown dialogs while using wayland, the dropdown menu will not be under the menu item.

Recording:
Screencast_20240413_213139.webm

Steps to reproduce:

1.Run linux and wayland (in my case fedora KDE wayland)
2.Have an ultrawide screen (works fine on my second normal screen)
3.Move the window so that the dropdowns should show up on the left half of the screen
4.Hover over the dropdown menu

Tested apps:

KiCad (wxWidgets 3.2.4)
Audacity

[vadz]

This really looks like a kwin bug to me, there is absolutely no reason for it to show menus on an ultrawide display differently than on a normal one.

Can you run GTK demo example on your system? You should see the same thing with its menus.

[JacekP1]

Apologies for the long delay in my response.

I have finally managed to compile a menu example using gtk3 toolkit. It does not show the same bug, the menu dropdowns show up in their proper place. Does that mean it's a kwin bug?

Regards,
Jacek Pawlik

[vadz]

No, if GTK sample works correctly, it implies that the problem is in wxGTK, but I have absolutely no idea where could it be because we don't seem to be doing anything related to the menu positioning in src/gtk/menu.cpp at all, letting GTK do it...

Which GTK menu example did you compile, exactly? Could you please leave a link to it or just attach it here please?