Avoid resizing featured image

Hi, is there a way to avoid the theme to resize the featured image? I always use images 1200×675 as posts’ featured image, but Maxwell theme shows the image cropped and resized to 810×580.

Can the theme avoid cropping and resizing, showing the image without altering it, in the original resolution, and just scaling it to fit the column width without losing resolution?

This would help for SEO purposes, as Google prefers sites with large featured images. As Google explains here, sites showing large images “at least?1200 px wide and enabled by the?max-image-preview:large?setting” are more likely to be selected by Google Discover. However, if we use Maxwell theme, the page presents an image 810px wide. Would be great if the page showed the image in the original size, just adapting it to the column width.

Thanks for helping!
Carlo

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