1475966 - The page crutchfield.com is not to render properly while Tracking Protection Basic is enabled

Status: RESOLVED WORKSFORME

(Web Compatibility :: Privacy: Site Reports, defect, P5)

Description

[Oana Arbuzov [:oanaarbuzov]]

[Environment:]
Browser / Version: Firefox Nightly 63.0a1 (2018-07-15)
Operating System: Windows 10 Pro, Mac OS X 10.13

[Prerequisites:]
    1. Tracking Protection Basic enabled.
[Steps to Reproduce:]
    1. Navigate to  https://www.crutchfield.com/car/carselector.aspx?lp=%2FCar%2Foutfitmycar%2Fmycar.aspx
    2. Observe the page.
        
[Expected Behavior:]
The page is rendered correctly (no elements are overlapped)
 
[Actual Behavior:]
The page is not rendered correctly ("How we help you shop for car A/V" section overlaps main section)

[Note:]
    1. Also reproducible with Tracking Protection Strict.

Comment 1

[Oana Arbuzov [:oanaarbuzov]]

Looking at the devtools console, here are the blocked resources:
The resource at “https://px.owneriq.net/stas/s/crutch.js” was blocked because tracking protection is enabled.[Learn More] carselector.aspx 
The resource at “https://stats.g.doubleclick.net/dc.js” was blocked because tracking protection is enabled.[Learn More] carselector.aspx 

So there were domains to test:
- px.owneriq.net
- stats.g.doubleclick.net

I opened the URL in a fresh browser profile (Firefox Nightly 63, uMatrix installed, normal mode) and loaded the page. The page is displayed correctly.

I disabled the Spoof Referrer option in uMatrix and then whitelisted px.owneriq.net. Nothing changed.
I then whitelisted crutchfieldonline.com (and all related domains) in order to see stats.g.doubleclick.net domain.
Refreshing the page the sections got overlapped.

The other resources (px.owneriq.net, stats.g.doubleclick.net) didn't help. 

So in conclusion:
- crutchfieldonline.com which is not listed in Blacklist or Entitylist

Comment 2

[Oana Arbuzov [:oanaarbuzov]]

Attachment: uMatrixResults_Render.png

Added uMatrix results.

Comment 3

[François Marier [:francois]]

I can't reproduce this: https://screenshots.firefox.com/hmMdQAgkAYb7WPZA/www.crutchfield.com

Oana, do you see something different than the above screenshot?

Comment 4

[Oana Arbuzov [:oanaarbuzov]]

François , it seems that the issue is no longer reproducible on Windows 10 Pro, but it is still reproducible on MacOS 10.13.5 (like in the initial Webcompat issues).

Comment 5

[François Marier [:francois]]

I was able to reproduce it on a Mac as well: https://screenshots.firefox.com/jvU9TjdYA49NT2WV/www.crutchfield.com

It is however extremely flaky. The layout seems to fix itself when one of these is true:

1. the devtools are opened (!)
2. doubleclick.net is whitelisted
3. owneriq.net is whitelisted

I guess this is too broken to really be worth keeping track of. The only reasonable fix is server-side.

Comment 6

[Thomas Wisniewski [:twisniewski]]

The page seems to be rendering fine for me now in strict mode.