https://instantview.telegram.org/checklist#6-2-2-cover-images "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." And there is class "postermain"
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https://instantview.telegram.org/checklist#6-2-2-cover-images
"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."
And there is class "postermain"