Zoom selector changed from square to portrait

I looked at how the magnifier worked (by generating multiple images) to see if I can make it work the way I want it to (not cropping the image in the zoom frame).
For some reason it changed from the normal square to a longer (more height than width) portrait mode.
Does anyone know what could cause this?
I’ve checked image classes (max-width, width, height and max-height) but no results yet. If I tick “crop” the zoom frame itself is a square, but the selector is still portrait mode. Which means parts of the image are not zoomable, since it shows the usual square image.
Help greatly appreciated!

https://wordpress.org/plugins/yith-woocommerce-zoom-magnifier/