Bug 402098

SUMMARY
I set an alternative shortcut to navigate through windows (ctrl+right and ctrl+left) but I cannot go through multiple windows, I can only reach the next window or previous.

STEPS TO REPRODUCE
1. goto system setting -> window management -> task switcher
2. switch from main tab to alternative
3. add new alternative keys to navigate forward and back
   set to ctrl+right and ctrl+left
4. I get ask if I want this because it is in use already, I confirm.

OBSERVED RESULT
I cannot reach all windows, just the last one.
I can still switch with alt+tab as expected but ctrl+right goes only one window, I cannot go multiple steps, same when going back.

EXPECTED RESULT
I expect same behavior as with alt+tab, that I can go through multiple windows by keeping ctrl held down and pressing right or left repeatedly.

SOFTWARE/OS VERSIONS
Windows: 
MacOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.8.4
KDE Frameworks Version: KDE Frameworks 5.28.0
Qt Version: Qt 5.7.1 (built against 5.7.1)

ADDITIONAL INFORMATION
Linux (x86_64) release 4.9.0-8-amd64
newly installed debian stretch
The xcb windowing system