Created attachment 179173 [details]
Bug showcase

SUMMARY
GTK appmenus initially open in the wrong position until moving the cursor over a different menu entry (see attached video)

STEPS TO REPRODUCE
1. Open an affected GTK app (tested with DBeaver and KiCad)
2. Click on an appmenu item that isn't the first
3. Move the mouse over to a different appemenu item

OBSERVED RESULT
Appmenu opens under the first menu entry initially ("File"), then updates to the current menu entry once hovering over a different entry.

EXPECTED RESULT
Appmenu opens initially under the menu entry that is being hovered over during the click, then updates to the new menu entry once hovering over a new one.

SOFTWARE/OS VERSIONS
KDE Plasma Version: 6.3.2
KDE Frameworks Version: 6.11.0
Qt Version: 6.8.2
Kernel Version: 6.13.5-zen1 (64-bit)
Graphics Platform: Wayland
Processors: 32 × AMD Ryzen 9 3950X 16-Core Processor
Memory: 62.7 GiB of RAM
Graphics Processor 1: AMD Radeon RX 7900 XTX
Graphics Processor 2: llvmpipe

ADDITIONAL INFORMATION
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