I'm seeing this on my 4K laptop monitor using ksnip 1.8.1 build 1686.d6b138b
3840 x 2160 225% scaling.

I've seen this behaviour before, in prior versions.
Just wanted to share.

This is what I see on my monitor:

As soon as I start 'take screenshot' with ksnip screen is aprox 1/4 of the monitor: (1/225% ?)

This is the area I select for screenshot:

And this is the result: