By jason on 12/04/2015
Sharing Facebook content seems easy, and for the most part it is. If you're developing a web asset that is going to be shared on Facebook, you want to take advantage of the open graph, and insert Facebook open graph meta tags onto your page; this way, you can specify the proper title, thumbnail, url, description, etc: http://davidwalsh.name/facebook-meta-tags - which is used when sharing url via Facebook.
When you're developing something, and try sharing it on Facebook, Facebook caches the web page and preview, so, you don't see your latest work. There are some work-arounds for this, such as appending a url parameter: www.mysite.com/?v=1
This is different to Facebook than: www.mysite.com/
So, you can see the latest work by updating the ?v=X url parameter.
Even better, is that you can post your url to the Facebook debug tool, and Facebook will respect your work.
https://developers.facebook.com/tools/debug/og/object - this will save you a lot of trouble...if you're like me.
Whew..saved me some grief. Hope it will help you, too.