I have the Firefox Search by Image for Google plugin
It looks for identical images, and it also gives a link to 'Visually similar images', which displays the same results as search by URL I think.
I just checked and yes, it shows the same results.
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mofaha ┐( ˘_˘)┌ ʅ(́◡◝)ʃ,
Thu 21 Nov 2013, 5:47,
archived)