It is obligatory to use a cover image if the image is present on the page and described in the source as “featured-img”, “cover”, “lead_img”, “main_image”, etc.
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Reference: https://instantview.telegram.org/checklist#6-2-2-cover-images
For this case, the marked figure is "entry-featured-image"
Yes it is optional if the image is below the title/subtitle, but the class name ...