1266813 - webrequest.jsm fails on modifying both request and response headers.

Status: RESOLVED DUPLICATE of bug 1232849

(WebExtensions :: Untriaged, defect)

Description

[alexmehler]

User Agent: Mozilla/5.0 (Windows NT 6.3; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0
Build ID: 20160407164938

Steps to reproduce:

Hi, 

i yesterday tried to implement webrequest.jsm to modify the response headers "Cache-Control" and "Expires" of images from a website. 
so i made a test addon and used a slightly modified code of this tutorial ,
https://developer.mozilla.org/en-US/docs/Mozilla/JavaScript_code_modules/WebRequest.jsm
its the last snippet on that site. i console.log´d everything so the code is running fine.
make a new profile, enter the url of an image, load it ...




Actual results:

... go to about:cache , look for the image and then you will see that its cached with the original response headers instead of the modified ones.  


Expected results:

it should cache the images with the modified headers but it doesn´t.

then as a blind test i implemented another version based on nsihttpchannel and look at the cache and it shows the modified header correctly. 

after that i also tested the other methods and "ressource blocking by url" is working correctly and modifying request headers doesn´t work.