How to modify a request in Fiddler?

Question

I\'m looking for a simple way to intercept a web request and modify the contents of the request (mainly POSTs) using Fiddler.

This is

Answer 1

I use fiddler 4.6.3. You can try this if you are submitting a web form.

Note the post request when you submit a form. Let that request remain in fiddler. Lets modify the request in Fiddler.

1 - Right click request > check "unlock for editing".

2 - Inspector tab > Modify form fields such as username, password etc. in Body section.

3 - Right click request > Replay > Reissue request.

Done ! The only problem with this approach is that you modify the old request. In Charles proxy, this is done in 2-3 clicks vs the many clicks in Fiddler. Plus, you don't have to mess the old request.