Fiddler for OS X Beta is now available for download. Try it out today and let us know what you think.
Over the years, we have received numerous requests from our user community to provide a Fiddler build for OS X. While Fiddler for Windows can be used as a proxy for apps running on OS X, there is still great value in being able to run Fiddler on OS X natively.
So we have ported the latest version of Fiddler to the Mono Framework which in turn supports OS X—and you can grab the beta bits today.
Once you download the new Fiddler for OS X file, follow these steps to get up and running with it:
While the Oct 2016 Fiddler Release for OS X increases development speed, this approach introduced some limitations, which you will find more details about in the next section.
Fiddler for OS X has the same familiar look that Fiddler for Windows has, however, it is built on top of the open source WinForms Mono implementation. The quality of that implementation is significantly lower than that of Microsoft WinForms, and this results in a less than ideal user experience. While we were aware of that when we began our work on the macOS version of Fiddler, we chose to go this way so that we can bring OS X support to life faster, not sacrifice the roadmap for Fiddler for Windows and base our future work on real world usage.
The most problematic areas in the UI for the beta 1 release are resizing the window and resizing elements inside the window. That oftentimes results in poor or laggy redrawing of all the affected elements. Quite often, though, hovering over or clicking on the affected areas will fix things.
Currently this effect is limited to Safari only and it happens only if you visited the site before opening Fiddler. Cleaning the browsing history (just the history not cache or cookies) for the affected site(s) fixes the problem.
Our preliminary research shows this problem occurs with websites using TLS versions greater than 1.0. The lack of Mono implementation of TLS 1.1 and 1.2 limits Fiddler for macOS to using TLS 1.0 only. Rather unfortunately, Fiddler TLS 1.0 connection comes after TLS 1.2 connection has been made to the same domain which doesn’t seem to be acceptable to Safari.
This is a hard limitation introduced by the current state of TLS implementation in the Mono framework. So Fiddler for OS X cannot use these protocols at present.
Fiddler for OS X Beta cannot display these at present. This is work in progress.
The initial version of Fiddler for OS X can be updated only manually.
This version of Fiddler for OS X will work for 60 days and then it will need to be updated.
Tsviatko is the Lead Developer for JustDecompile and Fiddler.