chain proxies

How do I chain proxies with this thing?
i.e. if I have another http proxy that I want to use but I also want to use this, how can I set that up?

Can the internal socket handler be wrapped one more time, before making the remote connection ?

Start by locating the internal socket handler and the code that establishes the remote connection; the issue names no files or tests. Clarify the expected proxy configuration and chaining behavior with maintainers, then define completion criteria and coverage for the selected setup.

Written by the indexing model from the issue text.