__computeUserIntendsAutoFill({ prevValue, curValue }) {
    const userIsAddingChars = prevValue.length < curValue.length;
    const userStartsNewWord =
      prevValue.length &&
      curValue.length &&
      prevValue[0].toLowerCase() !== curValue[0].toLowerCase();
    return (
      userIsAddingChars ||
      userStartsNewWord ||
      (this.__listboxContentChanged && this.__hadUserIntendsInlineAutoFill)
    );
  }
Computes whether a user intends to autofill (inline autocomplete textbox)
@param {{ prevValue:string, curValue:string }} config
@private