I'm not entirely sure what you're asking. Are you using Fiddler, or FiddlerCore?
Either way, Fiddler exposes many different ways to export data from a given session, depending on whether you want to include headers, only the body bytes, whether you'd like the body to be unchunked and decompressed, etc.
The simplest thing you can do is:
oSession.utilDecodeResponse(); // Remove chunking/compression
... but there are many other approaches depending on what exactly it is you're trying to accomplish.
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