Affected versions

• Firefox 70.a01

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 - Cross-site and social media trackers".
3. Go to Facebook and click on the shield icon.
4. Click on Cross-site Tracking Cookies.

Expected result

• The list is populated.

Actual result

• The list is empty.

Regression range

• I don't think this is a regression.

Additional notes

• If you blocked the Cross-site Tracking Cookies in about:preferences#privacy (in Custom mode) the list is populated at least with one site.

If you block Tracking Loads in Custom ("Tracking Content"), you will be blocking loads on the Level 1 Disconnect List + Social Trackers. If the loads are blocked, there are no cookies around to block. This might explain the empty "Cross-Site Tracking Cookies" list.

What are the settings? Can you provide the values of these prefs:
privacy.annotate_channels.strict_list.enabled
urlclassifier.trackingTable
urlclassifier.trackingAnnotationTable

Can you also provide the list of the trackers?

In the "Additional Notes", you mention that the list is populated when you block Cross-Site Tracking Cookies. Is that when protection on that page is enabled or disabled? If it is when it is disabled, this could make sense because now you are also allowing the Tracking Content and hence Tracking Cookies that were originally blocked may be present. What domains show up on the list?

Johann or Gary - can you followup on this next week while I'm out?

Please note the existence of bug 1574111 which I suspect is related to this bug.

I believe the explanation in the beginning of comment 1 is correct.

Talked to Johann about this and we agreed this can be marked duplicate of bug 1574111.

Also see bug 1576641