I had missed the proxies and it looks great. It would work well with FoxyProxy in my current setup. But I can't get it to work with my network socks5 proxy. I enter something like http://ip:port (which works well with FoxyProxy) but I get 'The proxy server is refusing connections'. Does the URL pattern look correct?
EDIT: I get the web page only when Firefox VPN is running presumably because then the connection is routed through Firefox VPN rather than my socks proxy, so the proxy feature is not working here for some reason.