Affected versions

• Firefox 74.a01
• Firefox 73.0b11
  *Firefox 72.0.2

Affected platforms

• Windows 10 x64
• Ubuntu 18.04 x64
• macOS 10.13

Steps to reproduce

1. Go to about:preferences#privacy.
2. Select Custom mode and make sure that everything is selected except "Cookies".
3. Go to https://www.boredpanda.com/ or any other site that has Social Media Trackers.
4. Click on the shield icon.

Expected result

• Social Media Trackers are displayed in the "Allowed" section.

Actual result

• Social Media Trackers are displayed in the "None Detected" section.

Regression range

• last good: 01-11-2019
• first bad: 04-11-2019
• I can't find the exact regression, because on the builds that between 02-11-2019 and 02-11-2019, Social Media trackers are not detected.

Additional notes

• If you select everything from Custom, Social Media Trackers are listed in the "Blocked" section.

Hi Erica — Is this regression something you can have someone take a look at soon?

Nihanth, any idea why this is happening?

On boredpanda.com, the social media tracker I see when blocked is www.facebook.com. The content blocking log for the anomalous case described in comment 0 is "https://www.facebook.com": [[8192, true, 1], [32768, true, 1], [131072, true, 13]]. So we're seeing LOADED_LEVEL1_TRACKING_CONTENT, COOKIES_LOADED, AND LOADED_SOCIALTRACKING_CONTENT.

So the UI is correctly putting this under None Detected, and the bug is that we are not recording a COOKIES_LOADED_SOCIALTRACKER. Investigating...

The code at [1] is responsible for emitting COOKIES_LOADED_{SOCIAL}TRACKER. The only reasons it wouldn't emit these two flags (which are both applicable to this case), is if the resource has not been classified as a (social) tracker yet, or if for some reason we can't get an nsIClassifiedChannel reference to the channel, or if there's an anomaly in GetThirdPartyClassificationFlags().

[1] https://searchfox.org/mozilla-central/rev/b1e51ad5613ad3d911cf42e3e525885ce2278915/toolkit/components/antitracking/AntiTrackingCommon.cpp#922

Even though this bug is a regression, it doesn't have a critical impact on users. Set to P3.

I've lost context.