Under what circumstances do normal URL-links (without image upload) in a Tweet automatically convert into an autoexpanded image/link-combination?
For example: Links to some newspaper articles show as link only while others convert into some kind of clickable thumbnail of the article itself.
Best Answer
This is related to a feature called Twitter Cards. After the site owner inserts specific meta tags to the page and validates it via Twitter, a Twitter Card will be displayed in addition to the link. There are various card types for different types of content.