System proxy settings dialogs allows configuring a proxy per http://, https://, ftp://, gopher://, however do not include ws:// or wss://.

Confirm that when using system proxy settings Chrome applies the same behavior as the host platform. Do they treat websocket requests as equivalent to http:// or https://, or do they bypass the per-proxy mappings and use SOCKS.

Based on Issue 889155 it appears that Chrome treats them as distinct protocols.

When configuring proxy settings using a chrome-specific method (policy, extensions, command line flag), we should probably support remapping ws:// and wss:// too.

When using PAC ws:// and wss:// are visible to the PAC script, however there is a compatibility hack when using the system proxy resolver that remaps them.