Error: The clear attribute on the br element is obsolete. Use CSS instead.
Error: The width attribute on the table element is obsolete. Use CSS instead.
Error: The cellspacing attribute on the table element is obsolete. Use CSS instead.
Error: Element option without attribute label must not be empty.
Using HTML markup checker such as:
https://validator.w3.org/#validate_by_uri
return many errors/warnings on PMA output, for example:
https://validator.w3.org/nu/?doc=https%3A%2F%2Fdemo.phpmyadmin.net%2Fmaster-config%2F
such as: