How to capture traffic on facebook without having it be the only tab of my firefox window

[Kyle]

Video Explaining My Issue


I was trying, as a test run, to capture the traffic from Facebook. I did what someone suggested in my previous post about removing the "https" and just using "facebook." I did that, clicked "Actions," and selected "Run Filter Set Now." I then refreshed the tab I was currently on, which was Facebook, and as you can see in the video link, no traffic was captured.

So, what am I supposed to do if I want to capture only the tab with Facebook traffic ? Do I really have to close my Firefox window, reopen Firefox, and have just one tab open with Facebook? Then, I would use Fiddler Classic. How is this realistic at all?

If anyone can please inform me how I can capture all of Facebook's traffic in the session list without any other traffic being captured-thus sparing me the hassle of sorting through the list to identify which traffic belongs to Facebook- that would be great. Otherwise, I see no reason to continue using Fiddler Classic or to subscribe.

[Nick Iliev]

Hey Kyle,

Your video suggests that you are not capturing any traffic at all from Firefox—with or without filters. That could be related to Firefox's proxy settings, which should be set to "Use system proxy settings".

Then, ensure that you have enabled the decrypt HTTPS option and that you have installed and trusted the Fiddler certificate. Finally, ensure you have started capturing through F12 or the app's menu.

If you prefer, you can configure your Firefox browser to use the Fiddler proxy explicitly through the manual mode (instead of using the system proxy settings), as shown in this documentation section.

As noted in the duplicate thread, the Fiddler application does not "recognize" different tabs and will capture traffic from all tabs opened from the specific browser instance (that uses the Fiddler proxy). So when your Firefox is configured to use the Fiddler proxy address and port (through the system proxy or explicitly through the manual settings), you will still have traffic captured from all tabs. Then, this traffic can be filtered through the "Filters" or a custom script in FiddlerScript.

As a side note, the Fiddler Classic application is free and not part of a subscription model. If you are interested - you can test Fiddler Everywhere, which is subscription-based and offers wider support for modern-day protocols. It also supports using Fiddler as a proxy in a sandboxed browser instance (only for Chromium-based browsers - and will capture traffic only from a specific browser instance) and has advanced filtering options.

 

Regards,
Nick Iliev
Progress Telerik