Does your firefox take 10-30 seconds to startup, even on an SSD? If you disconnect the internet, does it startup in a couple of seconds?

I’ve been trying to resolve this issue for a while and came across the answer. I thought I’d share with you guys, in the event that some of you are also having this issue.

The problem is resolved if you edit your "/etc/host" file (as root) and add:

127.0.0.2 %your hostname%

If you don’t know what your "hostname" is, you can get it by putting the following command in the prompt:

hostname

Here’s an example:

#<ip-address> <hostname.domain.org> <hostname>
127.0.0.1 localhost.localdomain localhost
127.0.0.2 unidentifiedFLYINGcarrots
::1 localhost.localdomain localhost

#Then save the file and restart Firefox.

#Thanks to Fadi R  

https://forum.antergos.com/topic/2142/fix-firefox-long-startup-time