Firefox – How to remove localhost from proxy exceptions in Firefox

firefoxPROXY

According to this, localhost is not forwarded to the proxy by default:
http://kb.mozillazine.org/Network.proxy.no_proxies_on

My question is: How do I remove localhost as an exception?

The "No proxy for" field in my proxy options in firefox is already empty, but localhost is not being forwarded to the proxy.

network.proxy.no_proxies_on in about:config is also already empty.

My particular scenario that I'm trying to get to work:

I have two Windows 10 machines: Proxy server A and client B

Server A is is running bitvise ssh server. Client B connecting to it as a socks 5 proxy via Putty. The server A has a local web server running on the localhost:9001 that I want to access in Firefox from the client B.

Best Answer

You have to change an additional setting in addition to removing localhost and 127.0.0.1 from the No Proxy For box. Set network.proxy.allow_hijacking_localhost to true in about:config.

This was changed recently. Source: https://bugzilla.mozilla.org/show_bug.cgi?id=1535581

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