Popup Error Feedback: Label element, aria-describedby, aria-controls and status
label[for]element is used to label form control.
requiredattribute to identify a form control is required.
aria-invalidattribute is used to identify a form control has an invalid value.
role="status"is used to autmatically announce errors in form controls.
aria-controlsis used to provide a programmatic reference to the error message, so assistive technologies could render information about the error (e.g. Braille).