Seeing duplicate http requests in server logs

I have started a small django application in my machine. When i have seen the request logs I figured out that It is actually logging the same requests twice.

After a little investigation, I disabled all of my add-ons in my browser and tried. To my surprise i din't see duplicate requests in logs After that.

After some trials I found that, If YSlow and firebug are enabled, Browser is sending duplicate requests. Otherwise i see 开发者_开发知识库only a single request in logs.

My machine is centos. And firefox version is 2.0.0.11. Yslow 2.0.1 and firebug 1.3.0

Did any body see this sort of issue? Any ideas what's going on actually?

Firebug and YSlow sending a request again if you have auto analysing activated. Or if not, when you open the network tab or starting the YSlow analysing.

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