Gwenview is installed from neon unstable and shows version 21.07.70.

SUMMARY
When using the tag editor's tag completion combo box, on wayland, the combo box pull down menu sometimes opens as a window. This only happens when the menu opens automatically when starting to type text.

STEPS TO REPRODUCE
1. Start gwenview with an image and open the tag editor.
2. Press a key letter on the keyboard where multiple tags already exist in the file system that start with that letter.
3. The combobox pull down menu will open (as expected).
4. Delete the text entered and type it again.

OBSERVED RESULT
A window is opened, with the title and icon for Gwenview and the content of the pull down menu. The window works like the pull down menu in it responses to keyboard navigation, typing additional text to filter down the list or clicking.

EXPECTED RESULT
A menu should be opened.
SOFTWARE/OS VERSIONS
KDE Plasma Version: 5.22.80
KDE Frameworks Version: 5.83.0
Qt Version: 5.15.3

ADDITIONAL INFORMATION
The behavior goes back and forth between a menu and a window - after a window opens, closing it and reopening it will show a menu, closing that and reopening again will show a window and so on.

Using just the mouse to open the menu by clicking the down arrow icon in the text box always shows a menu.