Squid not work under HTTPS made by GKE Ingress, but built Squid' Docker image work normally when run on Compute Engine

Question

■ In my case, HTTPS is required for Squid proxy, so I'm using GKE Ingress on Google Cloud for making HTTPS connection.

My bult Docker image can work as a proxy function on a VM(Compute Engine) or Service of TCP Load Balancer without any problems, but it does not function on GKE Ingress.

▼ I'm using sources as below (I don't know why, but I must use 4. and 5. to pass healthy checking on GKE Ingress)

1. Dockerfile

FROM ubuntu/squid

RUN apt update -y && \
    apt install -y nginx supervisor curl

RUN mkdir -p /var/log/supervisor
COPY supervisord.conf /etc/supervisor/conf.d/supervisord.conf

COPY squid/squid.conf /etc/squid/squid.conf
COPY index.html /var/www/html
COPY health.html /var/www/html
COPY nginx.conf /etc/nginx/conf.d/default.conf

EXPOSE 8080 80

ENTRYPOINT [ "/usr/bin/supervisord" ]
CMD [ "-c", "/etc/supervisor/conf.d/supervisord.conf"]

2. GKE Ingress(squid6-deployment.yaml)

apiVersion: v1
kind: Namespace
metadata:
  name: squid6
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: squid6-v01
  namespace: squid6
  labels:
    app: squid6
    env: v01
spec:
  replicas: 1
  selector:
    matchLabels:
      app: squid6
      env: v01
  template:
    metadata:
      labels:
        app: squid6
        env: v01
    spec:
      containers:
      - image: asia-northeast1-docker.pkg.dev/dev-project-01/dev-img-squid6/squid6:{{SHORT_SHA}}
        name: squid6
        ports:
        - containerPort: 8080
        resources:
          limits:
            cpu: 1000m
            memory: 1024Mi
          requests:
            cpu: 1000m
            memory: 512Mi
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  namespace: squid6
  name: squid6
  annotations:
    ingress.gcp.kubernetes.io/pre-shared-cert: "dev-ca-proxy-example-com"
    kubernetes.io/ingress.global-static-ip-name: "dev-ip-squid6-01"
    kubernetes.io/ingress.allow-http: "false"
spec:
  rules:
  - host: proxy.example.com
    http:
      paths:
      - pathType: ImplementationSpecific
        backend:
          service:
            name: squid6
            port:
              number: 80
---
apiVersion: cloud.google.com/v1
kind: BackendConfig
metadata:
  namespace: squid6
  name: dev-backend-k8s
spec:
  healthCheck:
    checkIntervalSec: 30
    timeoutSec: 5
    healthyThreshold: 1
    unhealthyThreshold: 2
    type: HTTP
    requestPath: /health.html
    port: 80
---
kind: Service
apiVersion: v1
metadata:
  namespace: squid6
  name: squid6
  annotations:
    cloud.google.com/backend-config: '{"default": "dev-backend-k8s"}'
spec:
  type: NodePort
  ports:
  - name: "http"
    protocol: TCP
    port: 80
    targetPort: 8080
    nodePort: 30081
  selector:
    app: squid6
    env: v01

3. squid.conf

http_port 8080

# local src
acl localnet src 192.168.0.1-192.168.255.255
acl localnet src 10.0.0.0/24     # Public subnet CIDR
acl localnet src 10.144.128.0/17 # Pod IPv4 address range
acl localnet src 34.119.224.0/20 # IPv4 service range
acl localnet src 130.211.0.0/22  # Google Healthy Checking
acl localnet src 35.191.0.0/16   # Google Healthy Checking

http_access allow localhost
http_access allow localnet

acl loadBalanerlIP src 34.110.152.xxx # HTTPS Load Balancer IP
http_access allow loadBalanerlIP

4. nginx.conf

server {
  listen 80;

  location / {
    root /var/www/html;
    index index.html index.htm;
    try_files $uri $uri/ /index.html =404;
  }

  include /etc/nginx/extra-conf.d/*.conf;
}

5. supervisord.conf

[supervisord]
user=root
logfile=/tmp/supervisord.log
logfile_maxbytes=50MB
logfile_backups=10
loglevel=info
nodaemon=true

[program:squid]
command=/usr/sbin/squid -N -f /etc/squid/squid.conf
stdout_logfile=/var/log/supervisor/%(program_name)s.log
stderr_logfile=/var/log/supervisor/%(program_name)s.log
autorestart=true

[program:nginx]
command=/usr/sbin/nginx -g "daemon off;"
stdout_logfile=/var/log/supervisor/%(program_name)s.log
stderr_logfile=/var/log/supervisor/%(program_name)s.log
autorestart=true

▼ Some figure about setup Squid Proxy

1. I can view Squid page via HTTPS normally before set it as proxy server on Windows. Can view Squid page normally via HTTPS URL

2. Proxy setting on Windows 11 Proxy setting on Windows 11

3. But, I cannot view any pages after setting up Proxy Server. I cannot view any pages after setting up Proxy Server.

★I've been using many days to researched, but I can't found solution to fix this problem. So, could someone give me guidance to fix this hard problem?