Change Jetpack's Infinite Scroll Button's Text

functions.php

<?php

function cone_change_infinite_scroll_btn_text() { 
    if ( is_home() || is_archive() ) { ?>
        <script type="text/javascript">
            var textCaption = '';

            if ( 'en-US' == $( 'html' ).attr( 'lang' ) ) {
                textCaption = 'Load More Posts';
            } else {
                textCaption = 'További bejegyzések'
            }

            infiniteScroll.settings.text = textCaption;
        </script>
    <?php }
}
add_action( 'wp_footer', 'cone_change_infinite_scroll_btn_text', 3 );