docs: add DNSLink lookup to Privacy Policy (#901)

PRIVACY-POLICY.md

@@ -1,7 +1,7 @@
 # **IPFS Companion Privacy Policy**
 
 <em>First Posted: 2019-02-15<br/>
-Last Update: 2020-05-08</em> ([change history](https://github.com/ipfs-shipyard/ipfs-companion/commits/master/PRIVACY-POLICY.md))
+Last Update: 2020-06-20</em> ([change history](https://github.com/ipfs-shipyard/ipfs-companion/commits/master/PRIVACY-POLICY.md))
 
 The IPFS Companion browser extension is owned by Protocol Labs Inc. and created
 by the IPFS Project. We know you care about how your personal data is used and
@@ -60,6 +60,11 @@ IPFS Protocols” experiments, websites will be able to detect you are running
 IPFS Companion. This behavior can be changed on Preferences screen by disabling
 mentioned experiments.
 
+If you are using DNSLink (its lookup is enabled by default), then IPFS node
+will be executing DNS queries for all domain names visited during browsing,
+and those queries will use DNS resolver configured in your operating system.
+To disable this behavior set "DNSLink lookup" to "Off" in Preferences.
+
 **Will We Ever Change This Privacy Policy?**
 
 We’re constantly trying to improve IPFS Companion, so we may need to change this