Connection settings in Firefox

Your organization or Internet Service Provider may offer or require you to use a proxy to connect to the Internet. Learn more.

Configuring Firefox to work with Burp Suite - PortSwigger

Using Firefox on MLML

Configure ubuntu proxy firefox - TellyPass

Configure Firefox to use the Putty SSH tunnel as a SOCKS proxy

Proxy settings in Mozilla Firefox

FiddlerCap with Firefox - Fiddler - Telerik

connection - Net Profiles caused trouble in Firefox proxy settings - Super User

Proxies for Firefox: step-by-step setup

Setting up a proxy in Mozilla Firefox on macOS

Basic Internet Security

How to Disable Proxy Server in Firefox

Proxy Server Settings - How to Make Proxy Server Settings for IE, Firefox, Chrome, MSN Messenger, Skype, CuteFTP Pro, Yahoo Messenger etc

How To Set Up a Proxy Server Connection in Firefox - GreenGeeks

Configuring Mozilla Firefox to Use a PAC File