It seems that you are using the standard Facebook Share button
in your application. If this is the case, this type of button has been officially deprecated by Facebook in favor of the Like button since July 2012. You can have a look at the article, which explains this on their official site http://developers.facebook.com/docs/reference/plugins/like/
(the exact section is "What happened to the old Share button").
As we rely on external scripts from Facebook to create the Share button we have no control over this functionality and whether Facebook will completely remove this button in the future (in which case we will be forced to remove it as well) or it will remain deprecated.
My advice is to use our styled Facebook button (for the full list of styled buttons, you can visit http://www.telerik.com/help/aspnet-ajax/socialshare-styled-buttons.html
) or the standard Recommend/Like button. This will ensure that you won't get these warning messages in your application.
the Telerik team
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