example of easy shortcodes you can add in functions.php

functions.php

<?php

add_shortcode( 'section-break', function($attributes = array(), $content = null) {
	return '<div class="article-body-section-break"></div>';
} );

add_shortcode( 'email-tease', function($attributes = array(), $content = null) {
	return Timber::compile('partials/newsletter.twig', array('context_class' => 'newsletter-signup--in-article', 'text' => $content));
} );