Prevent multiple submissions on RSForms

Sometimes multiple submissions are created by site visitors clicking rthe submit button repeatedly.

We can stop that by disabling the submit button after the first click and changing the button text to 'Sending ...' 

This is currently implemeted on Biomin.

To fix:  Go to componenets > RSForm! Pro > Manage Forms > Choose the form > Form Properties > CSS and Javascript

Enter the following code in the Javascript area:

<script>
jQuery(document).ready(function($) {
    $('.rsform-submit-button').on('click', function() {
        $(this).prop('disabled', true).text('Sending...');
        $(this).closest('form').submit();
    });
});
</script>