Update : No longer required for WPLMS 2.4, check WP Admin – LMS – Settings switch
Please add the given code in your wplms-customizer.php file in wplms-customizer plugin :
add_action('wp_head', 'add_unit_auto_complete', 9);
function add_unit_auto_complete() {
?>
<script>
jQuery(document).ready(function ($) {
$('.unit_content').on('unit_traverse',function(){
$('#mark-complete').trigger('click');
});
});
</script>
<?php
}