'keep below others' window disappears on invoking app menu

[Robert Marshall]

I have gkrellm running (in 15.04/plasma) and have set it so that it appears on
all workspaces and have the option set 'keep below others'
I also have mouse-1 bound to Application Launcher

If I move to a workspace where only gkrellm is visible and click on the
desktop (set to Desktop view) gkrellm disappears! It reappears once I
select something off the menu or click elsewhere on the desktop

Anyone else seeing this, worth a bug report? I've just investigated and
I see the same thing when I set a konsole to be 'keep below others' so I
guess it happens for any window type

Robert
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Robert Marshall               twitter: @rajm