Best workflow to release updated config files without breaking already existing customization
Solution 1:
We use template files like config_template.ini. After an update the user can diff their local config.ini with the current config_template.ini. If they only see differences in the values, then that is probably just a usual customization. If they see a new value in the template, they should come up with an apropriate value for their installation. And if the template is missing a value they have in their local config that means this value is no longer needed.