October 28, 2019 · Web Squid

Force Firefox use remote DNS while proxying

IPv6
Firefox supports IPv6 by default, which may cause connection problems on certain systems. To disable IPv6 in Firefox:

In the address bar, type about:config and press Return.

The about:config "This might void your warranty!" warning page may appear. Click I accept the risk! to continue to the about:config page.
In the Search field, enter network.dns.disableIPv6.
In the list of preferences, double-click network.dns.disableIPv6 to set its value to true.
DNS Prefetching
Firefox attempts to speed up loading new websites by using DNS Prefetching, which can cause page load errors with some system configurations. To disable DNS Prefetching:

In the address bar, type about:config and press Return.

The about:config "This might void your warranty!" warning page may appear. Click I accept the risk! to continue to the about:config page.
Hold down the Ctrl key while you click in the list of preferences, select New, and then select Boolean.
In the Enter the preference name field, enter network.dns.disablePrefetch and click OK.
Select true when prompted to set the value and click OK.

  1. Disable IPv6 (Key : network.dns.disableIPv6)
  2. Disable dnsPrefetch (Key : network.dns.disablePrefetch)
  3. Disable dns cache (Key : Network.dnsCacheExpiration)
  4. Clear History
  5. Restart Firefox App