in Install Plone from its packages – Install — Plone Documentation v6.0, it is written: “ You will be presented with a series of prompts. You can accept the default values in square brackets (
[default-option]) by hitting the Enter key, or enter your preferred values.”
A warning about forbidden characters should be added (it would be even better for this warning to be displayed by the script). At least the characters
', which are likely to be used in the “description” step, cause errors.