chromium/third_party/blink/web_tests/fast/forms/text/input-appearance-autocomplete-suggestion-maxlength.html

<input id="input" maxlength="5">
<script>
input.focus();
internals.setSuggestedValue(input, 'MisterLongName');
internals.setAutofilled(input, true);
input.setSelectionRange(0, 5);
</script>