When someone Facebook "likes" a blog post of mine, FB automatically sets the image to be used. It does not select the image from my blog post, instead it chooses one of the thumbnails from my related posts plugin.
Even before I had the related posts plug-in, Facebook instead chose an image I have placed just before the comments form as the default image.
Is there an easy way to somehow tell Facebook that it should choose the image from within the blog post (I only ever post one image per blog post) to use as the thumbnail when someone "likes" my page?
I have over 500+ published posts so I need a way to retroactively apply this.
I am currently using the official Facebook plug-in. I also tried using a Facebook Open Graph Featured Image plug-in, which fixed the issue but caused a problem whereby Facebook was reporting multiple og:url's when using the debugger which I believe is a bigger problem.
Debugger - Facebook Developers
Here is the current message I receive in the debugger:
"og:image is missing. The og:image meta tag is necessary for Facebook to render a News Feed story that generates a high click-through rate."
Any ideas anyone?
Here is an example URL from my blog that you can try in the debugger:
How To Make Vitamin C From Citrus Peels
Thanks in advance,