Deploy traefik with docker stack on Windows Server

Question

I want to run traefik on a docker swarm cluster powered by Windows Server 2019.

It works while using docker network create and docker service create commands directly.

But a seemingly identical compose file does not work. Any help is appreciated.

PowerShell commands:

# create network
docker network create proxy --driver overlay --subnet 11.0.0.0/24 --gateway 11.0.0.1

# start traefik
docker service create `
    --name traefik `
    --constraint node.role==manager `
    --publish 80:80 `
    --publish 8080:8080 `
    --mount type=npipe,source=\\.\pipe\docker_engine,target=\\.\pipe\docker_engine  `
    --label traefik.port=8080 `
    --network proxy `
    stefanscherer/traefik-windows `
    --docker `
    --docker.domain=traefik `
    --docker.endpoint=npipe:////./pipe/docker_engine `
    --docker.network=proxy `
    --docker.swarmMode `
    --docker.watch `
    --api `
    --defaultentrypoints=http `
    --entryPoints='Name:http Address::80' `
    --logLevel=DEBUG

Compose file:

version: '3.7'

services:
  main:
    image: stefanscherer/traefik-windows:v1.7.12
    networks:
      - net
    volumes:
      # pipe is available only on manager nodes
      - type: npipe
        source: \\.\pipe\docker_engine
        target: \\.\pipe\docker_engine
    ports:
      - 80:80
      - 8080:8080
    deploy:
      placement:
        constraints: [node.role == manager]
      # for dynamic traefik configuration add labels here
    command:
      # for static traefik configuration add options here
      # alternative: add configuration file via volumes
      - --docker
      - --docker.domain=traefik
      - --docker.endpoint=npipe:////./pipe/docker_engine
      - --docker.network=proxy
      - --docker.swarmMode
      - --docker.watch
      - --api
      - --defaultentrypoints=http
      - --entryPoints='Name:http Address::80'
      - --logLevel=DEBUG

networks:
  net:
    driver: overlay
    name: proxy
    ipam:
      driver: default
      config:
        - subnet: 11.0.0.0/24

After posting this question, I decided it might be a docker bug and opened this issue.