I've updated 2 systems to Plasma 5.9.3 and ksnapshot seems slightly broken.
I could not get a snapshot of "Window Under Cursor" no matter what I did
I got Full Screen. In the case of one system with dual monitors I got
both screens. I changed Window Behavior to "Click to focus" just in
case. That made no difference.
I tried this on a VM that had not been updated and it works as
expected. So, I think the Plasma update is causing this.
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