Facebook "Like" icon
The Facebook "Like" option will be cached after a customer loads a product page containing the Social Media Sharing module, and should appear almost immediately when viewing other pages that include this feature.
Note: When you add a new product, or first enable the Social Media Sharing feature for your products, you may notice a time delay between publishing your changes and when Facebook recognizes the "Like" function on the product page. This time delay issue is on Facebook's end, and because of this, Yahoo! cannot change how these updates are handled by Facebook.
When this delay occurs and a user clicks the "Like" icon on a product page, a message noting that Facebook is unable to reach the page will be displayed beside the "Like" icon. In some cases the delay lasts for only 1 to 5 minutes after publishing, and in other cases, can take an average of 15 minutes to resolve. If this does not resolve after an hour, then any errors seen as a result of clicking the "Like" icon may be as a result of a different issue.
Facebook Open Graph Meta Tags
When you provide a Facebook Application ID, Facebook Open Graph Meta Tags will be added to your store's index page. These meta tags should not affect page load time for your store.