The example in the README section Exposing Ports is out dated. The release notes for Bitcoin Core v0.18.0 state:
The rpcallowip option can no longer be used to automatically listen on all network interfaces. Instead, the rpcbind parameter must be used to specify the IP addresses to listen on. [...]
This PR adds -rpcbind=0.0.0.0 to bind on all interfaces of the container in the example.
The example in the README section Exposing Ports is out dated. The release notes for Bitcoin Core v0.18.0 state:
This PR adds
-rpcbind=0.0.0.0
to bind on all interfaces of the container in the example.