Configure fiddler to not capture requests for certain domains

When you are debugging using fiddler, fiddler generally captures requests from all the domains. An easy way to not capture requests from certain domains is to use the build in “filters” tab in fiddler. Use the “Hide the following hosts” dropdown and key in the list of all the domains that you want to hide.

If you want more granular control then you can override the OnBeforeRequest method in Fiddler’s script using Fiddler’s Script Editor.

static function OnBeforeRequest(oSession: Session) {        
        if (
        	oSession.HostnameIs("www.google.com") || 
        	oSession.HostnameIs("inbox.google.com") || 
        	oSession.HostnameIs("13.client-channel.google.com") || 
        	oSession.HostnameIs("d.docs.live.net") || 
        	oSession.HostnameIs("slack.com") || 
        	oSession.HostnameIs("notifications.google.com") || 
        	oSession.HostnameIs("play.google.com") || 
        	oSession.HostnameIs("cello.client-channel.google.com") || 
        	oSession.HostnameIs("lp-push-server-777.lastpass.com") || 
        	oSession.HostnameIs("ssl.gstatic.com") || 
        	oSession.HostnameIs("clients4.google.com") || 
        	oSession.HostnameIs("clients1.google.com")
        )
        {  
            oSession["ui-hide"] = "hidden";    
        }
        //code omitted for brevity
}
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Fiddler not capturing traffic from browsers

Sometimes when you are trying to capture browser traffic for debugging, Fiddler does not capture the same.
One of the options to try is to make sure that the “Use Filters” checkbox is unchecked in the “Filters” tab in Fiddler.

You can also troubleshoot filters to see which filters are hiding your traffic.

If this does not work then you might have an extension (Like ZenMate or TunnelBear) installed that might have messed with your traffic. You might need to disable those extensions to ensure that Fiddler captures all the traffic from the browser.

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Show traffic from only certain hosts in Fiddler

A lot of times when we “show traffic” in Fiddler, way too much traffic gets logged. To cut the “noise” out, we want to show traffic from only certain hosts. To do this:

  • Check the “use filters” checkbox.
  • In the “Show only the following hosts” textbox, type the names of the hosts separated by colon.
  • If you have several similar hosts then you can use wildcards also.
    Example: If you want to log the requests for drive.realpage.com, photos.realpage.com then instead of listing each one of them, you can use *.realpage.com. See below for an example

FiddlerFiltersTab

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