Fix problem Image on sharing posts to Facebook

When you share a post on Facebook, it will display a thumbnail picked from the post page along with a short description of the post. But in many cases Facebook fails to  identify the correct image and description

Fixing the Wrong Image Problem.
You might have noticed that comment avatars, and other  irrelevant images come up when you share the post on Facebook . The solution to this is to specify the image in the page meta data. We will be using open graph tags for the same.
Go to Template > Edit HTML and just above

</head>

Paste the following code snippet.

<b:if cond='data:blog.postImageThumbnailUrl'>
<meta expr:content='data:blog.postImageThumbnailUrl' property='og:image'/>
<b:else/>
<meta content='https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgwNKxDbov-AtRXmJRqgNX1w56DPU9F88vOVKV_a6TaTz4OHN3SpDYF1auEWur_TUu2HnuFOr2hR6DE-mene2lzAU_E7NF3DEeGZ3AzwAavR-ULTPtoA7MQOIRRwquiZ_io32kU43xsvjg/s1600/bloggertofree.png' property='og:image'/>
</b:if>

You can alter the image URL in the above snippet. That image will be used when no post thumbnail is present.