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How do you create comments for fields in a ui_component form?
I can do it like this when building the form with php:
$fieldset->addField( 'url', 'text', [ 'name' => 'url', 'label' => __('URL'), 'title' => __('URL'), 'required' => false, 'note' => 'Can be an absolute or relative path.' ] );
I can't find how to achieve this in an xml form component.