marcbacon · August 17, 2016 22:27
diff --git a/Featured Image Instructions.php b/Featured Image Instructions.php
 // Add text to featured image meta box
 add_filter( 'admin_post_thumbnail_html', 'mytheme_featured_image_instruction');
 function mytheme_featured_image_instruction( $content ) {
    return $content .= '<p>Optimal size is 1410 x 260 pixels.</p>';
 }
	// Add text to featured image meta box
	add_filter( 'admin_post_thumbnail_html', 'mytheme_featured_image_instruction');
	function mytheme_featured_image_instruction( $content ) {
	return $content .= '<p>Optimal size is 1410 x 260 pixels.</p>';
	}