Problems with "Advanced Network Configuration" for wired connection

I have installed MATE on 19.10.1 on an RPi4 and recently updated to 20.04.

From the start, NetworkManager worked erratically with the wired connection, especially as I needed to set up a static IP. I eventually solved the issue with in an inelegant workaround, but I have now found the reason for the problem and the proper solution from "Wimpey's World" at:

The reason is that netplan is managing the connections, rather than NetworkManager. The solution is to add two files:

  1. Create /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg
    with the content:

network: {config: disabled}

  1. Create /etc/netplan/01-network-manager-all.yaml
    with the content:

network:
version: 2
renderer: NetworkManager

This solved all the issues and now "Advanced Network Configuration" works well.

Thank you Wimpy. I've been looking for the right solution for two months.

Maybe these details should be added to the official tutorial at: