I reviewed your screenshot and it appears you're speaking about Telerik Fiddler? The forum you posted this is for UI for Universal Windows Platform
, if you need assistance with Fiddler, you can post in the Fiddler forums
That said, I can answer you question as to how to get fiddler to work with Firefox. For future questions, please post in the Fiddler forum so that you can get the proper support engineer to assist.
You need to do the following:
For more information and to see how to configure Firefox manually, please see the Fiddler Documentation on how to manually configure Firefox
Lance | Tech Support Engineer, Sr.
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