"Search by image" should use google's thumbnail, in case the original is a dead link.

[lovelacehq]

One of the main uses of "Search by image" is when you try to view the image directly and you get a dead link, in which case you can easily find other versions of it by using google's thumbnail instead of the original image.

At the moment, when you click on "Search by image", you get "The URL doesn't refer to an image or the image is not publicly accessible." because you're feeding a dead link to Google's image search.

Alternatively, you could check whether the link is dead or not, and then use the thumbnail, or just make this a preference so people can choose the behavior. Personally I think using the thumbnail all the time is pretty reliable.