here is my stack config for portainer, or otherwise known as docker-compose.yml if you prefer that route. I added notes after # for reminders for myself, maybe they help you.

Portainer -> Stacks -> Add Stack:

Name: nginx-pm

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##

## Docker Compose File: NGINX Proxy Manager

## Function: Reverse Proxy

##

## Documentation: https://nginxproxymanager.com/setup/#running-the-app

## https://nginxproxymanager.com/

##

## Updating NGINX? Make sure to backup v1/data + v1/letsencrypt from Ubuntu VM,

## then make sure volume mapping reflects v1 data, not v2/v3 as it creates

## new ones every update/redeployment. It's bugged.

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version: '3.8'

services:

app:

container_name: nginx-pm

image: 'jc21/nginx-proxy-manager:latest'

environment:

- PGID=1000 #echo $GID to get this

- PUID=1000 #echo $UID to get this

ports:

- '80:80'

- '81:81'

- '443:443'

volumes:

- /home/YourUSERNAMEHere/data/nginx-pm:/data #host:container mapping

- /home/YourUSERNAMEHere/data/nginx-pm/letsencrypt:/etc/letsencrypt #host:container

logging:

driver: "json-file"

options:

max-file: "10"

max-size: "200k"

restart: unless-stopped