user6770522 Reporter
	Description • 8 years ago

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:48.0) Gecko/20100101 Firefox/48.0
Build ID: 20160728203720

Steps to reproduce:

1. Create a simple web server that serves HTML files with Content-Type "application/octet-stream". See attached "server.py" and "test.html".
2. Create a Web Extension and override the Content-Type using "chrome.webRequest.onHeadersReceived.addListener". See attached manifest.json and "background.js".
3. Activate the Web Extension in Firefox (via about:debugging).
4. Start the simple server and issue a request (e.g. http://localhost:8080/test.html).


Actual results:

The browser prompts the user to download the HTML file.


Expected results:

The browser should display the HTML page as a normal web page.

	Giorgio Maone [:ma1]
	Comment 2 • 8 years ago
mozreview-review

Comment on attachment 8793306 [details]
Bug 1304331: Support setting the Content-Type header from WebRequest observers.

https://reviewboard.mozilla.org/r/80078/#review78812

Thanks for the fix. Just out of curiosity, why did you add console in Extension.jsm?

	Kris Maglione [:kmag] Assignee
	Comment 3 • 8 years ago
mozreview-review-reply

Comment on attachment 8793306 [details]
Bug 1304331: Support setting the Content-Type header from WebRequest observers.

https://reviewboard.mozilla.org/r/80078/#review78812

I went to copy the line that added it into WebRequest.jsm so I could use it for debugging, and realized that it had been removed by the patches for bug 1287010. I meant to fix that in a separate patch, though.

	Kris Maglione [:kmag] Assignee
	Comment 4 • 8 years ago

https://hg.mozilla.org/integration/mozilla-inbound/rev/83a0cb757881b0eb3e0339794b22f0b4c6390e30
Bug 1304331: Support setting the Content-Type header from WebRequest observers. r=mao

	Carsten Book [:Tomcat]
	Comment 5 • 8 years ago
bugherder

https://hg.mozilla.org/mozilla-central/rev/83a0cb757881

	Liz Henry (:lizzard) (relman/hg->git project)
	Comment 6 • 8 years ago

Kris, is this a fix you are looking to uplift?

	Kris Maglione [:kmag] Assignee
	Comment 7 • 8 years ago

I'm considering it. I want to see how often it's used and how it goes over on nightly first, though.

	Kris Maglione [:kmag] Assignee
	Comment 8 • 8 years ago

I could only find two extensions in the Chrome store that do this:

https://chrome.google.com/webstore/detail/modify-content-type/jnfofbopfpaoeojgieggflbpcblhfhka
https://chrome.google.com/webstore/detail/l%C3%B6veliness/mompnkcmpbopandjnddeecgeeojegohc

with less than 4k users total. There aren't any WebExtensions for Firefox that do, yet.

It might be a good idea to uplift this to Aurora once it's had a week or two to bake. I'm not sure it should go to beta. Either way, we should document the limitation and the versions it affects.

	Kris Maglione [:kmag] Assignee
	Comment 9 • 8 years ago

Comment on attachment 8793306 [details]
Bug 1304331: Support setting the Content-Type header from WebRequest observers.

Approval Request Comment
[Feature/regressing bug #]: Bug 1232849
[User impact if declined]: This prevents extensions from modifying a common header, which may be necessary for their functionality, and which they should reasonably expect to work. Those extensions will likely unexpectedly fail in versions of Firefox without this fix.
[Describe test coverage new/current, TreeHerder]: The functionality in question has relatively good automated test coverage, and additional tests have been added for this bug.
[Risks and why]: Low. The changed sections of code are all wrapped in try-catch blocks so that any error is treated as a simple inability to modify the header, and will therefore silently revert to the previous behavior. Any issues should simply manifest as an incomplete fix, rather than causing problems we wouldn't otherwise have seen.
[String/UUID change made/needed]: None.

	Gerry Chang [:gchang]
	Comment 10 • 8 years ago

Hi Florin, can we have some QA's help to verify this?

	Gerry Chang [:gchang]
	Comment 11 • 8 years ago

Comment on attachment 8793306 [details]
Bug 1304331: Support setting the Content-Type header from WebRequest observers.

Fix a Web Extension related issue which will be in 51. Take it in 51 aurora.

	Carsten Book [:Tomcat]
	Comment 12 • 8 years ago
bugherder uplift

https://hg.mozilla.org/releases/mozilla-aurora/rev/a13ac8658440

	Victor Carciu
	Comment 13 • 8 years ago

Verified as fixed in :
Win7x64 - FF Nightly(52.0a1) 2016-10-06
        - FF Aurora(51.0a2)  2016-10-06

Win10x32 - FF Nightly(52.0a1) 2016-10-06
         - FF Aurora(51.0a2) 2016-10-06

	Will Bamberg [:wbamberg]
	Comment 15 • 8 years ago

I've added a browser compat note about "Content-Type":
https://developer.mozilla.org/en-US/Add-ons/WebExtensions/API/webRequest/onHeadersReceived#Browser_compatibility

Does this cover it?

	Will Bamberg [:wbamberg]
	Comment 16 • 7 years ago

Marking as dev-doc-complete, but let me know if I need anything else here.

	Kris Maglione [:kmag] Assignee
	Comment 17 • 7 years ago

I think that probably covers it.