I try to share the article or web page but the story does not show the image when sharing for the first time but when i share for the next time, image is coming.
Checked in FB Debugger Also, same result.image not coming for the first time , next time it is coming.
<html class="no-js" lang="ar" dir="rtl" data-ng-app="mApp" xmlns:fb="http://ogp.me/ns/fb#">
<meta property="og:title" content="mytitle"/>
<meta property="og:url" content="http://mytest.com"/>
<meta property="og:image" content="http://mytest.com/1-773128.jpg"/>
<meta property="og:description" content="ffff2024"/>
<meta property="og:site_name" content="ggggggg"/>
<meta property="og:type" content="ARTICLE"/>
<meta property="fb:app_id" content="2444444444444"/>
https://developers.facebook.com/docs/sharing/best-practices#precaching lists ways to avoid this problem, by either
scraping new articles upfront via API, or
specifying the image dimensions via OG meta tags as well.
UPDATE
This solution with iframe is not working anymore! Worked since yesterday 06 February 2017. Facebook just set X-Frame-Options as DENY so you cannot load the sharer url in an iFrame. I'm figuring out another workaround.
I struggled to find a solution for this facebook bug (adding og:image:width and og:image:height was not enough).
Finally I came up with a workaround that worked: I added an hidden iFrame with the sharer link in the page footer; in this way the facebook crawler check the page once is loaded and, when you click facebbok share button in the first time you can see the shared image!
Example:
<iframe style="width: 0px; height: 0px; margin: 0px; padding: 0px;" src="https://www.facebook.com/sharer/sharer.php?u=http%3A%2F%2Fwww.example.com"></iframe>
来源：https://stackoverflow.com/questions/32505477/facebook-share-story-image-does-not-appear-for-first-time