I have a love/hate relationship with Firefox's new TRR (trusted resolver) feature that does it's own DNS. (Link here: https://blog.nightly.mozilla.org/2018/06/01/improving-dns-privacy-in-firefox/)
At home, on my WiFi, I've got awesome control and I really DON'T want Firefox to subvert it. Everywhere else, I love the TRR feature.
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