web scraping - Facebook Meta tags parsing -

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if add link website facebook, acts if doesn't have open graph meta tags , shows link. have meta tags on page.

in fact, after go https://developers.facebook.com/tools/debug , enter link there shows scraping done fine.

then, if post link again, link displays correctly.

why happen? can think of 1 alternative - facebook has workers scrape links posted, if first time link encountered. once scraped, other posts same links displayed scraped data. debug scraper has priority input data instead of workers.

is case?


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