RealVNC Enterprise5.3 or later

RFB 005.000

VNC:
  Protocol Version: 5.0
  Security Types:
    5: RA2
    13: RealVNC
    129: Tight Unix Login Authentication
    133: RealVNC

HTTP/1.1 400 Bad Request
Server: squid/3.5.12
Mime-Version: 1.0
Date: Mon, 29 Apr 2024 22:33:48 GMT
Content-Type: text/html;charset=utf-8
Content-Length: 3533
X-Squid-Error: ERR_INVALID_URL 0
Vary: Accept-Language
Content-Language: en
X-Cache: MISS from IPRENT.CN
X-Cache-Lookup: NONE from IPRENT.CN:6666
Via: 1.1 IPRENT.CN (squid/3.5.12)
Connection: close