Hi @misrael365
I hope you are doing wel.
You will need to create some custom coding.
If you are using PHP you can use some hooks like:
add_filter( 'forminator_field_hidden_field_value', function( $value ){
if( $value === 'cookie_custom_value' ){
$value = .. your cookie value,
} return $value;
} );
Use the code on your child theme or as a mu-plugin following this guide: https://wpmudev.com/docs/using-wordpress/installing-wordpress-plugins/#installing-mu-plugins
Create an hidden field > Custom value and use “cookie_custom_value” as default value.
The filter will update the value and return data based on what you entered on
$value = .. your cookie value,
For example, you can make a new verification if a cookie exists and append it.
https://www.php.net/manual/en/reserved.variables.cookies.php
For localStorage ( Works for cookie too ) you can append the new value using JavaScript https://www.w3schools.com/jsref/met_storage_getitem.asp and update the field value: https://www.geeksforgeeks.org/jquery-set-the-value-of-an-input-text-field/
Best Regards
Patrick Freitas