Websocket not working

[whytf]

Information

https://whatismybrowser.com/w/KMGQ3AL

Help request

Problem

I have proxmox servers in my network and from past with using proxies i know they need websocket support to open terminal in them etc. but now the proxied page it's just blank white, in chrome console it spams Failed to load resource: the server responded with a status of 501 () or Uncaught (in promise) {message: 'A listener indicated an asynchronous response by returning true, but the message channel closed before a response was received.

What I have tried

I looked at documentation of websockets for nginx at it seems everything is included in the generated config, like include nginxconfig.io/proxy.conf but i have no idea why it is not working.

Screenshots

blank white page

Config

https://pastebin.com/mLA9mNVw