Jay Versluis

Show Me The Cookies displays all current cookies your site is using. Once activated, you can find this list under Appearance – Cookies.
Furthermore you can display this list to your visitors by placing the shortcode [cookies] into any post or page.
WordPress uses several cookies under the hood by default. If you’d like to filter these out, you can use the shortcode [cookies-nowp]. If you like, you can replace the default separator between the cookie name and its value by adding your own string between the opening and closing shortcode tags, for example [cookies] ==> [\cookies].
This plugin is based on code by David Artiss, who kindly made it available on GitHub. I’ve wrapped it up into this standalone plugin.
To find out more about what cookies are and what can be done with them, please read https://en.wikipedia.org/wiki/HTTP_cookie

Show Me The Cookies

Shows a list of all current cookies on your site, both for admins and visitors (optional).

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.

Show Me The Cookies vs LH Localforage