Reply To: Slider above home page content but not as page header

[Tom]

Merry Christmas! 🙂

Try this instead:

add_action( 'generate_inside_container','add_slider_to_container' );
function add_slider_to_container() {
    if ( is_front_page() ) : ?>
        <div class="grid-container">
            <?php echo do_shortcode( '[metaslider id=913]' ); ?>
        </div>
    <?php endif;
}