Bug 432201

SUMMARY
configuring vertical-scroll to do any switching (which is on the desktop basically the only purpose of the wheel) does not do it. just does nothing.

STEPS TO REPRODUCE
1. configure desktop>mouse actions
2. add/configure existing button 'vertical-scroll' to do 'switch desktop', apply
3. on free desktop area (VD>1) scroll the mouse, nothing happens.

OBSERVED RESULT
same doing nothing for switch window or activity

EXPECTED RESULT
desktop/window/activity switches. 

SOFTWARE/OS VERSIONS
Operating System: Fedora 32
KDE Plasma Version: 5.18.5 (newest available plasma version from fedora)
KDE Frameworks Version: 5.75.0
Qt Version: 5.14.2
Kernel Version: 5.10.8-100.fc32.x86_64
OS Type: 64-bit

ADDITIONAL INFORMATION
this IS working fine on:
Operating System: Fedora 31
KDE Plasma Version: 5.18.5
KDE Frameworks Version: 5.73.0
Qt Version: 5.13.2
Kernel Version: 5.8.18-100.fc31.x86_64
OS Type: 64-bit

i don't know, if this could be a pure fedora issue. the mouse-wheel does work as a scroll action on eg kwrite properly.