I noticed that I'm getting an empty Trackers subpanel on a YouTube video, see the screenshot. In the browser console, I got the content blocking log: await gBrowser.selectedBrowser.getContentBlockingLog() "{ \"https://www.google.com\": [[32768, true, 1]], \"https://www.youtube.com\": [[32768, true, 1], [536870912, true, 6]], \"null\": [[32768, true, 1]], \"https://pubads.g.doubleclick.net\": [[32768, true, 1]], \"https://www.google.ca\": [[8192, true, 1], [32768, true, 1]] } " I bet it is the null origin that is confusing something here...

Hmm, in a new container tab, I can reproduce this on the homepage of youtube immediately after pageload. This is from the console: await gBrowser.selectedBrowser.getContentBlockingLog() "{ \"https://www.youtube.com\": [[32768, true, 1], [536870912, true, 6]], \"https://pubads.g.doubleclick.net\": [[32768, true, 1]], \"https://ad.doubleclick.net\": [[32768, true, 1]], \"https://googleads.g.doubleclick.net\": [[32768, true, 1]], \"https://www.google.ca\": [[8192, true, 1], [32768, true, 1]], \"https://accounts.google.com\": [[32768, true, 1]], \"https://securepubads.g.doubleclick.net\": [[32768, true, 1]] } "

Hm, given that content blocking log the frontend seems to behave correctly to me. The log mostly contains cookie loads and a loaded tracker for google.ca, which is probably on the strict list?

Oh hmm, so we're OK with having cases where the user sees an empty list here?

Ah, hm, good point, we should probably talk about this during triage...

Steps to reproduce the issue using Steve's test page: 1) Turn on Standard mode in Content Blocking (tracking cookies blocked, tracking protection only in private mode) 2) Go to https://senglehardt.com/test/cookie_restrictions/embedded_strict_image.html 3) Control Center says Trackers are present (but not blocked). 4) Open the Trackers subpanel. There are not trackers listed. What is the reason why this is happening? Is it because of the following: The Trackers subpanel appears based off of Tracking Annotations that use the strict list. As long as a single tracker appears from the strict list, the subpanel arrow will appear. Then, when we decide what to display in the trackers subpanel, we filter out items not on the strict list. If that is the case, then in order to fix this, we'd have to filter out based on strict/basic list before the user ever opens the subpanel. Which is a potential performance issue for the Control Center.

Solution as discussed in our meeting today - In the trackers subpanel, when only trackers from the strict list are present and we are using the basic list for TP, write: None detected on this site

Bumping to P1

If P1 means that this should be fixed in 65, I disagree. We have many more important issues to fix in 65 which take priority over this.

Note that with bug 1509691 fixed, this doesn't impact youtube.com.

We will mitigate the issue over in bug 1511751. In the meantime this is not a P1.

Yes, thanks. Mitigation is a P1, but not this underlying issue.