In the next release of Baserow we’ll be fixing the root cause of this issue which is:
The user running our web server inside our docker image is not root. The error you had was this user didn’t have permissions to bind to port 80.
This capability is now set by default in Docker engine versions 20.10 > (https://github.com/moby/moby/pull/41030) . However prior versions of Docker crash, and I believe Portainer/Synology is using an older version.
The fix we’ve made is to change the user that runs the internal Caddy http server to instead run as root (just like it does in the offical Caddy/http/nginx etc docker images), so it can bind to port 80. This will mean Baserow will just work out of the box without any extra docs/steps needed next version 
.