Cropped and square Thumbnail’s

Hello,

I will be selling magazines, and need images to appear as they are, rectangular.

My product images look as they should, perfect.

Issue is the Thumbnail’s, they are square and cropped. I need them to appear as original, rectangular.

Contacted theme support, “Porto”. They stated, “images are coming from the WooCommerce plugin our theme has nothing to do with it”

I played around with the following code:
ul.product_list_widget li .product-image img{height:100px !important;}

It make it rectangular, but still crops and stretches image.

Note: Everything is running latest updates.

Any help appreciated!

Site in question

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