Is it possible in Firefox to use a proxy with authentication?

Question

User identification

In Firefox 35, I set my proxy in the network settings, but when I try to open the page, the login and password are not requested (just The connection has timed out). Is there such a possibility in the fox at all?
The proxy is 100% live.

Answer 1

https://support.mozilla.org/en/questions/926378
Similar problem with a solution.
I use the FoxyProxy extension, which allows you to specify a login / password in advance and not wait for a request (and much more)