browser uses a DNS server

[sasbag]

Either I misunderstood something in the description, or...
Here's the situation:
If the browser uses a DNS server other than the system's,
then all of the browser's connections will be displayed as IP addresses.
And those outgoing connections that were previously blocked by DNS name
are no longer blocked by IP address, meaning the rules created for sun.org don’t work for 82.165.239.195
Debian OS, Little Snitch for Linux 1.0.9

[starkjohann]

It depends: If it uses an encrypted DNS server, then yes. We have no way to break up the encryption to see the names. If it's plain port 53 DNS, it should still work.

If you want to use DNS encryption, please configure it system-wide and disable the Unix domain socket of systemd for DNS lookups: In /etc/nsswitch.conf look for the line starting with hosts: and remove the resolve option. The line should look like this:

hosts: files myhostname mdns4_minimal [NOTFOUND=return] dns

This change ensures that DNS lookups are routed through port 53 on the loopback interface where Little Snitch can inspect the packets before they are encrypted.