featured image from flickr url : fail

i’m trying to set my featured images by entering a link to the image from my flickr account. when i enter the link to the image i get a red X next to it as if the flickr link isn’t valid. i’ve had others try the same thing to make sure it wasn’t an individual permissions problem. the found the same issue. any idea why this would be happening? is it a flickr thing? is it a wordpress thing?

i haven’t had any problem uploading the image from my computer and setting it that way but i’d rather not use that option as it severely compresses my images to the point where i can’t stand to look at them.

thanks for any suggestions!