STR: 1. Enable privacy.trackingprotection.enabled pref 2. Compare the results of loading http://www.theguardian.com/us in an e10s and non-e10s windows RESULT: The non-e10s window blocks the banner ad header, but the e10s window does not.

This is because of the third party checks from https://bugzilla.mozilla.org/show_bug.cgi?id=1042377.

Brad recommends that we fix this bug early in M4.

Let's triage this in M4 like comment 2 says.

(In reply to [:mmc] Monica Chew (please use needinfo) from comment #1) > This is because of the third party checks from > https://bugzilla.mozilla.org/show_bug.cgi?id=1042377. Sounds like that's being taken care of by bug 1049299's patch (per bug 1042377 comment 11), which should land soon. Are we confident that the isThirdPartyChannel issue is the only thing breaking tracking protection with e10s?

I just downloaded a build from Blake's try push, and tracking protection did not work in an e10s window. This will require more investigation. Leaving myself needinfo'ed to check again after Blake's patch is landed.

Filed https://bugzilla.mozilla.org/show_bug.cgi?id=1088183 which should hopefully have a similar fix to https://bugzilla.mozilla.org/show_bug.cgi?id=1049299

This should be fixed now.

Verified as fixed using : FF 38 Build Id:20150208030206 OS: Win 7 x64, Ubuntu 12.04 x86, Mac Os X 10.8.5