The sign up form fails Web Content Accessibility Guidelines (WCAG 1.3.1, WCAG 3.3.2) because the input field for the email address isn’t associated with a label. Simply tweak the current code so that the input field is a child of the label element:
Currently:
[label]Email address: [/label]
[input type=”email” name=”EMAIL” placeholder=”Your email address” required=””]
improved:
[label]Email address:
[input type=”email” name=”EMAIL” placeholder=”Your email address” required=””]
[/label]
(Also blogpost here https://www.brucelawson.co.uk/2019/making-mailchimp-for-wordpress-more-accessible/)