Adding more virtual desktop is throttled: when clicking "+ Add" multiple times in a row with short intervals (~250ms..400ms or shorter), some clicks will be ignored (IOW the number of new desktops < the number of clicks made.)
When I tried to click the button as fast as I can, I was only able to add 4 virtual desktops per second on average.
This is annoying even when I want to add 2 more virtual desktops: I make 2 clicks at a rate of a normal double-click, and this results in only one virtual desktop being added.
STEPS TO REPRODUCE
Should add as many virtual desktops as the number of button clicks. There should not be noticeable latency for user actions.
(available in About System)
KDE Plasma Version: 5.21.5
KDE Frameworks Version: 5.83.0
Qt Version: 5.15.2
Using Chrome Remote Desktop which might add some latency (presumably ~50..100 ms).