Bug 1141814 made us disable speculative connect and DNS prefetching when the privacy.trackingprotection.annotate_channels pref is set by setting mLocalBlocklist to true here: <https://hg.mozilla.org/mozilla-central/rev/fb18b507a912#l4.22> This is bad because according to bug 1122691, doing this can regress page load performance by about 3%. We only need to do this if we're actually going to block such loads, since we'd be saving time by not running the tracking junk at all. But we shouldn't be doing this merely to annotate channels.

Comment on attachment 8819360 [details] [diff] [review] Ensure that speculative connect and DNS prefetching aren't disabled when annotating tracking channels Review of attachment 8819360 [details] [diff] [review]: ----------------------------------------------------------------- Thanks!

Pushed by eakhgari@mozilla.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/688f10a74c64 Ensure that speculative connect and DNS prefetching aren't disabled when annotating tracking channels; r=mayhemer