Created attachment 179400 [details]
Visual example of the missing text in the dropdown

SUMMARY
Under window management, when I edit or create a new rule, all of the combobox drop down menus display no text, or simply highlight the selection where no text is included. The options can still be selected and the selected option still normally/correctly displays in the main area.  

Upon opening the ComboBox journalctl prints this set of errors 1 time for each option that is supposed to be displayed:
<code>
qrc:/kcm/kcm_kwinrules/OptionsComboBox.qml:88: ReferenceError: bitMask is not defined
qrc:/kcm/kcm_kwinrules/OptionsComboBox.qml:101:17: Unable to assign [undefined] to QString
qrc:/kcm/kcm_kwinrules/OptionsComboBox.qml:115:13: Unable to assign [undefined] to QString
</code>

Hovering over the options will highlight the box as normal and produces this error each time a new element is hovered:
<code>qrc:/kcm/kcm_kwinrules/OptionsComboBox.qml:116: TypeError: Cannot read property 'length' of undefined</code>

STEPS TO REPRODUCE
1. Open Window Rules
2. Edit or Add new... any rule
3. Click a ComboBox (such as "Window class (application)") to open the drop-down list

OBSERVED RESULT
All ComboBox entries are empty and simply transparent or covered with a black selection as if it is hovered over.

EXPECTED RESULT
ComboBox entries should be listed plainly.

Operating System: Arch Linux 
KDE Plasma Version: 6.3.3
KDE Frameworks Version: 6.11.0
Qt Version: 6.8.2
Kernel Version: 6.13.6-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 9700X 8-Core Processor
Memory: 30.9 GiB of RAM
Graphics Processor: AMD Radeon RX 7900 XTX
Manufacturer: ASRock
Product Name: X670E Steel Legend