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                <p>パスワード表示機能を実装する際、 type="password" を type="text" へ切り替えると、「全角入力ができてしまう」「スクリーンリーダーで入力したパスワードが読み上げられてしまう」「ブラウザのオートコンプリートに記録されてしまう」といった数々の問題が起こりえます。そのため入力コントロールには手を加えず、 &lt;output&gt; 要素を使って表示する機能を考えてみました。</p>

	<label>Password <input type="password" id="password-input"></label>
	<button type="button" id="password-show-button" disabled="" aria-pressed="false">Show password</button>
	<output id="password-output" for="password-input" hidden=""></output>





                const passwordInputElement = document.getElementById('password-input');
const passwordOutputElement = document.getElementById('password-output');
const passwordShowButtonElement = document.getElementById('password-show-button');

passwordInputElement.addEventListener('input', (ev) => {
	const targetElementVelue =;

	passwordOutputElement.value = targetElementVelue;
	passwordShowButtonElement.disabled = targetElementVelue === '';

passwordShowButtonElement.addEventListener('click', (ev) => {
	const targetElement =;

	if (targetElement.getAttribute('aria-pressed') === 'true') {
		passwordOutputElement.hidden = true;
		targetElement.setAttribute('aria-pressed', 'false');
	} else {
		passwordOutputElement.hidden = false;
		targetElement.setAttribute('aria-pressed', 'true');