If you noticed that your Firefox installation takes significant time to connect to websites, there may be an easy solution. It will take you 30 seconds and save you a lot of time/annoyance in the future.

So:

• Type “about:config” in the address field and have Firefox open it as if it was an Internet URL. Firefox configuration page will appear.
• In the “Filter” text field, type: “dns” to get dns-related configurations only.
• Note the configuration named “network.dns.disableIPv6”. It’s value should be “true” (IPv6 should be disabled). If not, click on the value field to make it true.

Restart Firefox and enjoy faster connection times.