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<?php

/**
 * Functions which enhance the theme by hooking into WordPress
 *
 * @package WordPress
 * @subpackage Twenty_Nineteen
 * @since Twenty Nineteen 1.0
 */

/* function twentynineteen_body_classes() – Adds custom classes to the array of body classes. */
add_filter( 'body_class', 'twentynineteen_body_classes' );

/* function twentynineteen_post_classes() – Adds custom class to the array of posts classes. */
add_filter( 'post_class', 'twentynineteen_post_classes', 10, 3 );


/* function twentynineteen_pingback_header() – Add a pingback url auto-discovery header for single posts, pages, or attachments. */
add_action( 'wp_head', 'twentynineteen_pingback_header' );

/* function twentynineteen_comment_form_defaults() – Changes comment form default fields. */
add_filter( 'comment_form_defaults', 'twentynineteen_comment_form_defaults' );

/* function twentynineteen_get_the_archive_title() – Filters the default archive titles. */
add_filter( 'get_the_archive_title', 'twentynineteen_get_the_archive_title' );

/* function twentynineteen_post_thumbnail_sizes_attr() – Add custom sizes attribute to responsive image functionality for post thumbnails. */
add_filter( 'wp_get_attachment_image_attributes', 'twentynineteen_post_thumbnail_sizes_attr', 10, 1 );

/* function twentynineteen_add_ellipses_to_nav() – Add an extra menu to our nav for our priority+ navigation to use */
add_filter( 'wp_nav_menu', 'twentynineteen_add_ellipses_to_nav', 10, 2 );

/* function twentynineteen_nav_menu_link_attributes() – WCAG 2.0 Attributes for Dropdown Menus */
add_filter( 'nav_menu_link_attributes', 'twentynineteen_nav_menu_link_attributes', 10, 4 );

/* function twentynineteen_add_mobile_parent_nav_menu_items() – Create a nav menu item to be displayed on mobile to navigate from submenu back to the parent. */
add_filter( 'wp_nav_menu_objects', 'twentynineteen_add_mobile_parent_nav_menu_items', 10, 2 );
 

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