QGuiApplication::inputMethod()->locale() reports the wrong locale

With Ubuntu 24.04 and Ubuntu 22.04 the Qt QGuiApplication::inputMethod()->locale()
returns the ibus input locale the same you get with

ibus engine

Under the Ubuntu Session and also Xfce this does not follow the setting you do via the Ubuntu desktop environment which mainly goes to

/org/gnome/desktop/input-sources/mru-sources(sources) and can also be accessed via X11/XWayland and XkbGetNames() and friends. 

So we have the situation that for instance the German "ö" is displayed correctly in text based editors, but it is broken for short cuts, because the US keyboard is assumed returned as it is returned by QGuiApplication::inputMethod()->locale()

https://github.com/mixxxdj/mixxx/issues/14838

Expexted behaviour: 

QGuiApplication::inputMethod()->locale() shall report the layout that is used by the on screen keyboard.  

The Cinnamon and the KDE session seems to be not affected. On these systems ibus engine reflects the used keyboard layout.