Error correction suggestions

Rule ID	Error 4
Definition	When input error is automatically detected and suggestions are automatically known, the suggestions must be provided to the user (some exceptions).
Purpose	Users benefit from being informed of invalid input and on how to correct invalid input.
Mappings	HTML4 Legacy Techniques (Required) HTML5 and ARIA Techniques (Required)
WCAG Success Criteria	3.3.3 Error Suggestion (Level AA, Primary Success Criterion) Other Related Success Criterion:
Rule Category	Forms
Scope	Element
Target Resources	`textarea` and `input[type="text"]` elements, and ARIA textbox, gridcell and combobox widgets `select` `textarea`
Techniques	Add `aria-describedby` reference on the form control or widget to the suggestion information. Use a popup list to provide suggested values for valid input.
Informational Links	HTML 4.01 Specification: The `label` element Accessible Rich Internet Applications (WAI-ARIA) 1.2: aria-invalid H44: Using label elements to associate text labels with form controls ARIA1: Using the aria-describedby property to provide a descriptive label for user interface controls ARIA19: Using ARIA role=alert or Live Regions to Identify Errors