SUMMARY

I use the "All process,tree" view in ksysguard to suspend a process and its children when I don't use it (typically firefox, that nowadays spawns a lot of children processes).
Two problems:

1) If I select a "father" process and send SUSPEND to it, its children are not suspended. Wouldn't it be better if in tree view a SUSPEND signal (or any other) was sent to all the children as well?

2) Even if I use the tree view to see what the children of a process are and then select all of them plus the father and send SUSPEND, not all of them are always suspended. Sometimes it works, sometimes the father is still awake, sometimes some child stays awake.




STEPS TO REPRODUCE problem 1
1. go to tree view
2. select a process
3. send SUSPEND

OBSERVED RESULT
Only the process is suspended. 
Its children stay awake.

EXPECTED RESULT
It would be great if father and children were all suspended.

 STEPS TO REPRODUCE problem 2
1. go to tree view
2. select a process and all its children
3. send SUSPEND

OBSERVED RESULT
Not all the selected processes are suspended

EXPECTED RESULT
All the selected processes should be suspended

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 5.14.5
(available in About System)
KDE Plasma Version: 5.14.5
KDE Frameworks Version: 5.54.0
Qt Version: 5.11.3

ADDITIONAL INFORMATION