20 Sep 2019, 01:11
Do you have a link to the web page in question? It's a bit unclear, because the "preview image" itself has more function than just the option of showing on a page. It is used in 1) Page "og:image meta" data, which means it will be the image that is displayed when sharing on social networks, and 2) It is the preview image that will show if this page is listed on the PARENT page (which has it's own layout methods), and of course 3) at the top of the page itself, if you have chosen to display "preview image" in context for current page.
It is not clear to me if the screenshot is from option 2 or 3. Both have options to "crop" images (for a uniform layout), or NOT crop.