баян мля

I would suggest using the original by MS, as this is identical, only without credit to the original author.

(And I've compared them side-by-side, they're identical)

I guess it's just reposted because he used this background in his themes?

I doubt if it was originally by MS:

http://www.geekpedia.com/Picture322_Firefox-Scanner-Wallpaper.html

However I may be wrong.

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