Savelo Form Autosave silently saves everything visitors type in your forms — text, email, number, textarea, select, checkbox, radio — and brings it back if they navigate away and return, close the tab by accident, or their browser crashes.
All data is stored exclusively in the visitor’s own browser (localStorage). Nothing is ever sent to your server. Zero database queries on the front end.
<h4>Features</h4>
<ul>
<li>Universal form support — works with any HTML <code><form></code> element</li>
<li>Smart exclusion — automatically skips login, registration, password reset, and WooCommerce checkout forms</li>
<li>Security-first — never saves password fields; respects <code>autocomplete="off"</code></li>
<li>Contact Form 7 — saved draft is cleared automatically after a successful AJAX submission</li>
<li>Configurable expiry — 1 to 90 days; expired drafts are cleaned up silently</li>
<li>Restore notification — optional, auto-dismissing, fully customisable message</li>
<li>Clear on submit — optionally delete the draft when the form is submitted</li>
<li>Custom exclusions — exclude any form by CSS selector, by adding the <code>savelo-exclude</code> class, or the <code>data-savelo-exclude</code> attribute</li>
<li>Zero front-end dependencies — vanilla ES5 JavaScript, no jQuery required</li>
<li>Assets on demand — scripts and styles are never loaded in wp-admin</li>
<li>Translation ready — <code>.pot</code> file included</li>
<li>Clean uninstall — all plugin data removed when you delete the plugin</li>
</ul>
<h4>Privacy</h4>
All form data is stored in the visitor’s own browser via the localStorage API. No data is transmitted to your server or any third party. Compatible with GDPR-aware workflows. Users can clear their localStorage at any time via their browser settings.
<h4>How to exclude a form</h4>
<ol>
<li>Add <code>data-savelo-exclude</code> attribute directly to the <code><form></code> tag, or</li>
<li>Add the CSS class <code>savelo-exclude</code> to the <code><form></code> tag, or</li>
<li>Enter a CSS selector in Settings → Form Autosave → Exclude Forms</li>
</ol>

Savelo Form Autosave

Automatically saves form data to localStorage and restores it when the visitor returns. Zero server load. Works with any HTML form.

shawfactor

This plugin can greatly improve the user experience for your blog, by automatically and periodically saving fields like “just typed” comment (the content textarea input box in comment section), the visitors email, and vitors name (in the comment form).
The comment is saved using client side indexeddd (falling back to localstorage), this prevents loss of unsubmitted content.
This is similar like WordPress can remember your Name, Email, Website in comment area for the next visit, but WP Local Storage plugin extends this into next level, it can remember the actual unsaved comment (i.e. before hit submit button) so even the browser is crashed before the user hit save, it is okay! When the user came back, all “just type comment” will be still in there.
More importantly all data is saved client side, nothing is sent to the server. Thus maintaining visitor privacy!

LH Localforage

This plugin automatically and periodically saves the "just typed comment" so no data will be lost even if the browser crashes.

Savelo Form Autosave vs LH Localforage