Test if URL is accessible from web browser i.e. make sure not blocked by Proxy server

Question

I am serving my website from mywebsite.com. I host images on flickr so all images are loaded in the user\'s browser via get requests to flickr. Many of my websites users a

Answer 1

For facebook you can simply include the Facebook JS API and then test if one of the objects/functions it exports exists.

It would be better if you did not (ab-)use external hosts for your stuff. If you want a CDN, better use a real one...