HTTP Proxy with password won't work.
When connecting to a http proxy with a username and a password it says "Proxy server refused connection"
When connect to the same http proxy and turn off its Authentication, it works.
same bug with SwitchOmega & Smart proxy
Todas as respostas (1)
It should be fixed in the latest Nightly 122.0a1 (Bug 1851570). Can you confirm?