Forms · Complete runnable example

Dummy password visibility toggle

Reveal a fixed dummy password while preserving its text selection.

Try the example Read and copy the source

Live example

This preview runs in an isolated document. Clipboard writes and saved preferences may be blocked, and printing requires the standalone file. A dialog affects only the example. Reset reloads the original example state.

When to use it

Study the display behavior of a show-password control without entering real credentials. The example deliberately keeps its dummy field readonly and has no form or submit action.

Try the important details

  1. Select part of the fixed dummy value and use Show, then Hide. Verify the selection is retained.
  2. Tab to the button and activate it with Space or Enter; inspect its pressed state.
  3. Disable JavaScript to see the masked value and disabled reveal action.

How it works

  • Changing the native input type changes visibility without replacing its value.
  • The script captures selectionStart, selectionEnd, and selectionDirection and restores them after changing type. Pointer activation preserves input focus while keyboard focus remains on the button.
  • The accessible button name changes between Show dummy password and Hide dummy password to include its visible label. aria-pressed reflects whether the value is revealed. There are no logs, storage calls, or submission handlers.

The complete source

The preview, copied text, and downloaded file use this same document.

HTML 

<!doctype html>
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<html lang="en">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <meta
      http-equiv="Content-Security-Policy"
      content="default-src 'none'; style-src 'unsafe-inline'; script-src 'unsafe-inline'; img-src data: blob:; connect-src 'none'; form-action 'none'; object-src 'none'; base-uri 'none'"
    />
    <title>Take a careful look. | MRHTML example</title>
    <style>
      :root {
        color-scheme: light;
        --ink: #202b36;
        --muted: #596675;
        --line: #d5dde4;
        --blue: #2349c8;
        --pale: #edf1ff;
        --paper: #fff;
        --danger: #a32b30;
        font-family: Arial, Helvetica, sans-serif;
      }
      * {
        box-sizing: border-box;
      }
      [hidden] {
        display: none !important;
      }
      body {
        margin: 0;
        min-width: 0;
        padding: 42px 22px;
        background: #f2f4f7;
        color: var(--ink);
        line-height: 1.55;
      }
      main {
        max-width: 690px;
        margin: auto;
      }
      .brand {
        display: flex;
        align-items: center;
        gap: 10px;
        margin: 0 0 25px;
        color: var(--muted);
        font-size: 12px;
        letter-spacing: 0.04em;
      }
      .brand b {
        color: var(--ink);
        letter-spacing: -0.05em;
        font-size: 17px;
      }
      .brand b span {
        color: var(--blue);
      }
      .brand i {
        flex: 1;
        height: 1px;
        background: var(--line);
      }
      .card {
        background: var(--paper);
        border: 1px solid var(--line);
        border-radius: 18px;
        padding: 32px;
        box-shadow: 0 12px 36px #263a5110;
      }
      .eyebrow {
        margin: 0 0 12px;
        font-size: 11px;
        font-weight: 700;
        text-transform: uppercase;
        letter-spacing: 0.12em;
        color: var(--blue);
      }
      h1 {
        font-size: clamp(29px, 5vw, 38px);
        line-height: 1.13;
        letter-spacing: -0.04em;
        margin: 0 0 14px;
      }
      h2 {
        font-size: 20px;
        line-height: 1.3;
        margin: 0 0 14px;
      }
      p {
        margin: 0 0 18px;
      }
      .intro {
        color: var(--muted);
        max-width: 55ch;
      }
      .hint,
      .small {
        font-size: 13px;
        color: var(--muted);
      }
      .hint {
        margin: 9px 0 0;
      }
      .footer {
        font-size: 12px;
        color: var(--muted);
        margin: 20px 2px 0;
      }
      label,
      legend {
        font-weight: 700;
        font-size: 14px;
      }
      label.field {
        display: block;
        margin: 18px 0 7px;
      }
      fieldset {
        min-width: 0;
        margin: 22px 0;
        padding: 20px;
        border: 1px solid var(--line);
        border-radius: 10px;
      }
      legend {
        padding: 0 7px;
      }
      input,
      select,
      textarea,
      button {
        font: inherit;
      }
      input:not([type='checkbox']):not([type='radio']),
      select,
      textarea {
        width: 100%;
        min-width: 0;
        color: var(--ink);
        background: #fff;
        border: 1px solid #8896a5;
        border-radius: 7px;
        padding: 11px 12px;
        font-size: 16px;
      }
      input[type='checkbox'],
      input[type='radio'] {
        accent-color: var(--blue);
        width: 18px;
        height: 18px;
        flex: none;
      }
      textarea {
        display: block;
        resize: vertical;
      }
      button {
        border: 1px solid var(--blue);
        border-radius: 7px;
        min-height: 44px;
        padding: 10px 17px;
        background: var(--blue);
        color: #fff;
        font-size: 14px;
        font-weight: 700;
        cursor: pointer;
      }
      button.secondary {
        background: #fff;
        color: var(--blue);
      }
      button:disabled {
        cursor: default;
        opacity: 0.55;
      }
      input:disabled,
      select:disabled {
        background: #f0f2f5;
        color: #596675;
      }
      :focus-visible {
        outline: 3px solid #d46a20;
        outline-offset: 3px;
      }
      .actions {
        display: flex;
        flex-wrap: wrap;
        gap: 10px;
        margin-top: 22px;
      }
      .status {
        margin: 18px 0 0;
        font-size: 14px;
        min-height: 1.6em;
      }
      .error {
        color: var(--danger);
      }
      .panel {
        background: var(--pale);
        padding: 20px;
        border-radius: 10px;
        margin-top: 24px;
      }
      .panel p:last-child {
        margin-bottom: 0;
      }
      .row {
        display: flex;
        gap: 12px;
        align-items: center;
      }
      .sr {
        position: absolute;
        width: 1px;
        height: 1px;
        margin: -1px;
        overflow: hidden;
        clip: rect(0, 0, 0, 0);
        white-space: nowrap;
      }
      noscript p {
        border-left: 3px solid #9b6300;
        background: #fff4d6;
        padding: 12px;
        font-size: 14px;
        margin-top: 20px;
      }
      code {
        overflow-wrap: anywhere;
      }
      @media (max-width: 450px) {
        body {
          padding: 25px 14px;
        }
        .card {
          padding: 23px 19px;
          border-radius: 13px;
        }
        fieldset {
          padding: 16px 13px;
        }
        .brand {
          margin-bottom: 18px;
        }
      }
      @media (prefers-reduced-motion: reduce) {
        *,
        *::before,
        *::after {
          animation: none !important;
          transition: none !important;
          scroll-behavior: auto !important;
        }
      }

      .sample-tag {
        display: inline-block;
        padding: 5px 9px;
        border-radius: 4px;
        background: var(--pale);
        color: var(--blue);
        font: 11px monospace;
        letter-spacing: 0.04em;
        margin-top: 15px;
      }
      .password-row {
        display: flex;
        gap: 8px;
      }
      .password-row input {
        flex: 1;
        font-family: monospace;
      }
      .password-row button {
        flex: none;
        width: 72px;
      }
    </style>
  </head>
  <body>
    <main>
      <p class="brand">
        <b>MR<span>HTML</span></b
        ><span>THE INTERACTION NOTEBOOK</span><i aria-hidden="true"></i>
      </p>
      <section class="card" aria-labelledby="title">
        <p class="eyebrow">02 / Password visibility</p>
        <h1 id="title">Take a careful look.</h1>
        <p class="intro">
          A visibility toggle for a fixed dummy value. This example never asks
          for a real password.
        </p>
        <div class="sample-tag">READONLY DEMO VALUE</div>
        <label class="field" for="dummy-password">Dummy password</label>
        <div class="password-row">
          <input
            id="dummy-password"
            type="password"
            value="Demo-only-42!"
            readonly
            autocomplete="off"
            spellcheck="false"
            aria-describedby="password-help"
          /><button
            type="button"
            id="toggle-password"
            class="secondary"
            aria-controls="dummy-password"
            aria-pressed="false"
            aria-label="Show dummy password"
            disabled
          >
            Show
          </button>
        </div>
        <p id="password-help" class="hint">
          Select part of the dummy text, then toggle visibility. Your selection
          stays in place.
        </p>
        <div class="panel">
          <p class="small">
            A visibility control changes how a value is displayed. It is not
            encryption or a password-strength check.
          </p>
        </div>
        <p id="password-status" class="status" role="status">
          Dummy value is hidden.
        </p>
        <noscript
          ><p>
            The dummy value stays masked. Revealing it requires JavaScript.
            There is no submit action.
          </p></noscript
        >
      </section>
      <p class="footer">
        MRHTML example. Fixed dummy text only. No logging, storage, or
        submission.
      </p>
    </main>
    <script>
      (function () {
        'use strict';

        var input = document.getElementById('dummy-password'),
          toggle = document.getElementById('toggle-password'),
          status = document.getElementById('password-status');
        toggle.addEventListener('pointerdown', function (event) {
          event.preventDefault();
        });
        toggle.addEventListener('click', function () {
          var start = input.selectionStart,
            end = input.selectionEnd,
            direction = input.selectionDirection;
          var show = input.type === 'password';
          input.type = show ? 'text' : 'password';
          if (start !== null && end !== null)
            input.setSelectionRange(start, end, direction || 'none');
          toggle.setAttribute('aria-pressed', String(show));
          toggle.textContent = show ? 'Hide' : 'Show';
          toggle.setAttribute(
            'aria-label',
            show ? 'Hide dummy password' : 'Show dummy password',
          );
          status.textContent = show
            ? 'Dummy value is visible.'
            : 'Dummy value is hidden.';
        });
        toggle.disabled = false;
      })();
    </script>
  </body>
</html>