Google is testing a new feature or we can say it rolls out a new feature for its Featured Snippet named also covered on this page. Google is adding this feature below the main featured snippet, other topics the page covers, that hyperlink, anchor you down & then highlight that content.
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Here is a screenshot shared by Glenn Gabe Over Twitter.
Image Source: Twitter
When a User Clicks on it, it displays the anchor/ highlight. Check more in screenshot below:
Image Source: Twitter