Fiddler Ideas

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Make sure that filters apply to MS telemetry calls (e.g.

Microsoft telemetry calls to bypass the filters and add noise. If my filter says only show localhost, I don't expect to see calls to 

  • Guest
  • Jan 16 2018
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  • Eric Lawrence commented
    January 16, 2018 22:47

    Where specifically did you set the filter? If you right-click the Session and choose "Properties", what are the flags on the unexpectedly-visible Session?

    (By default, Fiddler doesn't hide sessions which resulted in HTTP Protocol Violation errors).

  • Dave Carlson commented
    January 25, 2018 20:22

    My host is slightly different:  I tried setting up a "Hide if URL contains" and "hide following hosts", but it still shows up.  I also tried adding a line in the custom rules file, but it still powers through.

    It is a protocol violation: "ProtocolViolationInRequest".

    Is there a special way I can block this specific request?

  • Dave Carlson commented
    January 25, 2018 20:22

    By block, I mean hide from the list.

  • Eric Lawrence commented
    January 29, 2018 16:41

    In the Session's Properties, you can see what exactly the protocol violation in the request is; depending on what the problem is, it reflects either a bug in the client (likely) or something that could be fixed in Fiddler.

    To cause a Session to be hidden regardless of protocol errors, you can add the word "STEALTH" to the UI-HIDE value, e.g.


    if (oSession.urlContains("")) { oSession["ui-hide"] = "STEALTH-boring boring boring...."; }
  • Rainer Koschnick commented
    February 6, 2018 09:48

    STEALTH doesn't work for me, those requests still show.

  • Eric Lawrence commented
    February 19, 2018 13:16

    Regarding the claim that "Stealth" doesn't work-- the most likely explanation is that you either wrote the rule incorrectly, or put it in the wrong place. Feel free to email me a SAZ capture demonstrating your issue. bayden at gmail dotcom.

  • James Brooks commented
    February 21, 2018 00:34

    I am also having issues with in Fiddler. My filter is on and set to "Show only the following Hosts" -- "localhost" yet I see both localhost and  I can right click on it and choose "Filter Now --> Hide v10.vort... yet after a few captures, it starts showing v10 again.  Always with 408 request body incomplete.

  • James Brooks commented
    February 21, 2018 00:41

    As a side note. Under "Filters" --> "Hide if URL contains" -->  does work in hiding it from Fiddler

  • James Brooks commented
    February 21, 2018 00:53

    Nope, spoke to soon. Adding "Hide if URL contains" did not work. Sorry.