Looks like Facebook disabled passing parameters to the sharer.
We have changed the behavior of the sharer plugin to be consistent with other plugins and features on our platform.
The sharer will no longer accept custom parameters and facebook will pull the information that is being displayed in the preview the same way that it would appear on facebook as a post from the url OG meta tags.
Here's the URL to the post: https://developers.facebook.com/x/bugs/357750474364812/