Teaser images at full height?

Will it be possible to show the article teaser images at their full height instead of the current cropped in half view?

Quote from GTB

You might have to use an image shown in the article resized to a certain size so it doesn't get cropped on height in the teaser. Making it something like a Google Ads banner style image so it's not that tall to suit being resized for the teaser image as well

I wanted to add a full size image as the teaser, not something that looks cut in half. I could do it with CSS using WCS 3.1 but can't figure out how to do it with 5.2.