Created attachment 138597 [details]
Reproducing bug; integrated terminal case

SUMMARY
Mouse pointer becomes unusable when it hovered over space delimiter and moved to delimited area

STEPS TO REPRODUCE
1. Left sidebar or integrated terminal must be active
2. Slowly move pointer to the left or down
3. When pointer reaches left (sidebar, workspace) or bottom (workspace, terminal) delimiter, it changes from cursor to something like this <-|->
4. It does not change back after pointer moved further left or down
5. Can be 100% reproduced with integrated terminal case, harder to reproduce with sidebar case, sometimes it happens, sometimes not

OBSERVED RESULT
Mouse cursor does not turn back to regular pointer
It turns back after it's moved back to the workspace area or moved outside of delimitated area

EXPECTED RESULT
Mouse works as expected

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: Arch Linux
(available in About System)
KDE Plasma Version: 5.21.90
KDE Frameworks Version: 5.82.0
Qt Version: 5.15.2+kde+r193-1