Spectacle 24.02.0, Plasma 6 Wayland, rectangular region, image gets enlarged. Known bug?

Arch, Plasma 6, Wayland, 4K monitor, 150% scaling. I pressed PrintScreen and Spectacle was opened with the captured full screen. Now, I wanted to crop the image to the bottom part, but when I clicked the “rectangular region” button, the image got bigger and only the top-left part of the captured image was displayed. I could not find a way to scroll the image.

Is this a known bug? Is there a way to get around this? I mean, some sort of way to scroll to the bottom?