Productivity: Debugging

Mozilla Firefox is unlike most Windows browsers in that it does not use the system’s proxy and certificate settings by default. That means that Firefox may require some additional configuration to work properly with Fiddler...

Over the years, the most interesting class of support requests for Fiddler are of the form: “My application or website is failing, but when I try to capture a repro with Fiddler, the problem goes away completely! How is Fiddler fixing it?”

A few weeks back, Jonathan Sampson noted that testing the HTML5 AppCache feature is a bit of a pain. One reason is that, in IE10, putting the browser into Work Offline mode is ineffective—the browser will detect that a network connection is available and exit the Work Offline mode automatically.

Recently, a Fiddler user contacted me to note that they discovered a client/server application which failed when the TLS version 1.1 option is enabled in Internet Explorer’s Advanced settings. They were surprised to find that when they attempted to use Fiddler to debug the communication, the connection was instead successful.

Yesterday, an updated Fiddler Beta was released, targeting .NET2 or .NET4. This update contains the usual set of bug fixes as well as a number of small features that I hope you’ll find useful.