youtube videos - how image for sharing to facebook

When i embed a youtube video (for example in the articles module) and then i want to share  the article to facebook. How can i insert the resource for a preview image for the facebook share dialog?

<meta property="og:image" content="https://thumbnails-visually.netdna-ssl.com/wealth-inequality-in-america_5134c6a02f651_w250_h250.jpg">

will be stripped inside the source code.

Hello mrtn!

As it relates to common part of security - then it's better to customize exact module (for example articles as posting is available only for admin) to allow insert similar tags into code of article. Keep this possiblity only for admin(s).

With the best regards, Leonid