Request header field X-*-User-Agent not allowed by Access-Control-Allow

[spartasolutions]

Running a demo unit (2.4 snapshot (insert current day here).

Currently using squid/squidguard for content filtering with ssl bump and certificates installed as trusted CA's.

Weirdly enough, running to one page I'm getting some websocket errors in regards to the request header. Full errors viewed from chrome are:

XMLHttpRequest cannot load https://tl.upwork.com/log/info. Request header field X-Odesk-User-Agent is not allowed by Access-Control-Allow-Headers in preflight response.
(unknown) WebSocket connection to 'wss://tl.upwork.com/wp?app=integrated&libVersion=2.43.0&tml=true&appVersion…ransport=websocket&X-Atmosphere-TrackMessageSize=true&X-atmo-protocol=true' failed: Error during WebSocket handshake: Unexpected response code: 200

From what it looks like it might just need to be added, just not sure how to go about doing that.

Thanks guys