In my case, I couldn't imagine configuring LittleSnitch to only allow certain hostnames from my browser. It has a "allow all traffic to 53/80/443" rule, otherwise most websites would flood me with hundreds of new LittleSnitch popups.
You'd think so, but the way I've set it up Little Snitch throws up a dialog box when a browser makes errant requests but otherwise remains silent. Most recently this caught Firefox trying to force DNS over HTTPS despite me having disabled it when it first became generally available. I suppose leaking DNS requests to Cloudflare isn't the worst thing in the world, but it would circumvent the ad blocking I've set up locally.
Ah so I just dug into the rules. What happened was a plugin made a DNS request to mozilla.cloudflare-dns.com. I've nothing special set up for Firefox, but basically no rules for plugin-container, so when a plugin tries to make a DNS request Little Snitch pops up an alert.
Not great I suppose, but better than nothing. Generally what I'll see for Firefox itself are requests for non 80/443 ports.
False dichotomy. Not only am I pretty sure Sonic isn't selling my DNS queries, I've already opted out of DNS over HTTPS. Refusing to respect the choices I've made is worse than not.
Besides, unencrypted SNI means that if my ISP wanted to get the hosts I was looking at, they could.
Is it? The best I could find was a bit from 2021 that showed 92 of the Alexa Top 1000 site supporting ESNI. If adoption has skyrocketed since then that's great… meanwhile Firefox is showing HN negotiated a TLS 1.2 connection with no ESNI support.
Can you elaborate on why you'd want to opt-out of DNS over HTTPS? I was under the impression that it was useful and good for privacy, but I may be misinformed.
It breaks DNS based blocking if you have it setup. Some people setup ad-blocking so that it encompasses their entire network and the way this works is that it silently drops DNS requests to ad domains on the edge of your local network.
And in some/many jurisdictions, your ISP is more regulated by your local government (also in regards to data protection) than cloudflare who has no obligation to you.