@mrskt what you are talking about is using the post_thumbnail_html hook to add a filter that alters the html that is returned by the function get_the_post_thumbnail(). This is not what you asked, you said you wanted to set the featured image for the post from a URL. While they are similar and may appear to have the same result, they are two different things.
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2022 was a big year for Advanced Custom Fields, with more capabilities, a new generation of ACF Blocks, a refreshed UI, and a new home. Our year in review post looks at advancements we’ve made and offers a glimpse of the future. https://t.co/HahJUCcyH4