Weird window behaviour on KDE 6

[dansity]

Describe the bug
I'm running opensuse tumbleweed, X11 session, kde 6, proprietary nvidia driver, default breeze dark theme.
When taking a screenshot the window behaves weird.
Out of the 30 something software I use only ksnip does this.

To Reproduce
Steps to reproduce the behavior:

1. Take a screenshot

Expected behavior
The window to be clear

Screenshots
Screen recording

Desktop (please complete the following information):

• OS: Linux
• Distribution in case of Linux: Opensuse Tumbleweed
• Window System in case of Linux: X11, KDE6
• ksnip version: 1.10.1
• How did you install ksnip: rpm package