I would like to set the Open in New tab as default option. So that when I add a new URL in a text I would like to automatically tick the box to open the link in a new tab.

I am running on Version 5.1.1. I tried to create the following plugin:

    <?php
/*
Plugin Name: New Tab Always
Description: Ensure that the new tab is always clicked.
Plugin URI: 
Author: 
Author URI: 
Version: 0.1
License: 
*/

add_action( 'admin_head', function() {
    global $pagenow;
    if ( $pagenow === 'post.php' ) {
        ?>
        <script>
            jQuery(document).ready(function($){
                var linkTarget = jQuery( '#wp-link-target' );
                if ( linkTarget.length ) {
                    linkTarget.prop( 'checked', true );
                }
            });
        </script>
        <?php
    }
});

However, I still get the old behavior of not having the button clicked.

Any suggestions what I am doing wrong?

I appreciate your replies!