When using a developer edition of uCommerce, uCommerce will write "uCommerce Developer edition" to the response. For some reason this also happens sometime for the binary image stream when an image is fetched from the media library. See output from fiddler below. Note the <div> before the png:

HTTP/1.1 200 OK
Via: 1.1 KV-TMG
Connection: Keep-Alive
Proxy-Connection: Keep-Alive
Content-Length: 43966
Expires: Fri, 26 Sep 2014 07:18:19 GMT
Date: Fri, 19 Sep 2014 07:18:19 GMT
Content-Type: image/png; charset=utf-8
Server: Microsoft-IIS/8.0
Accept-Ranges: bytes
Cache-Control: private, max-age=604800
Last-Modified: Wed, 17 Sep 2014 22:57:42 GMT
Content-Disposition: inline; filename="I_7391162202276_OKQ8_Naturavfettning_Koncentrat_4L_plastdunk_baksida_02.png"
X-AspNet-Version: 4.0.30319
X-Powered-By: ASP.NET
<div style="background-color:#53ACCA;color:#1C1C1C;font-size:20px;text-align:center;padding:5px;">uCommerce Developer Edition</div>�PNG

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