Bug 412610

SUMMARY
When dragging and dropping files between directories, with menu transparency enabled, background on the menu doesn't render properly.

STEPS TO REPRODUCE
1. Go into System Settings -> "Workspase Theme" and set "Breeze" as your theme. I'm not sure if bug is breeze specific, but different themes might not offer menu transparency.
2. Under Application Style -> Aplication Style -> Widget Style. Pick Breeze as application style and click more settings.
3. Under transparency set 50% opaque.
4. Have blur effect enabled (not sure if necessary)
5. Open dolphin, split screen and drag and drop some file from one directory to another. 

OBSERVED RESULT
Menu for selecting what to do with file (move, copy, link) has weird color.

EXPECTED RESULT
Menu for selecting what to do with file (move, copy, link) has working transparency.


ADDITIONAL NOTES
This might not be issue with Dolphin, but rather some other element of the system.

SOFTWARE/OS VERSIONS
Operating System: KDE neon 5.16
KDE Plasma Version: 5.16.5
KDE Frameworks Version: 5.62.0
Qt Version: 5.12.3
Kernel Version: 5.0.0-29-generic
OS Type: 64-bit
Processors: 4 × Intel® Core™ i5-4690K CPU @ 3.50GHz
Memory: 7,7 GiB