Wordpress shows random output beginning with flush_rules(); - php

Question

I already think I know the problem, there is a <?php somewhere or somewhere there is written <? and it makes the site crash but I don't know where it is.
Now I don't ask you to look through the whole code but if you know where I would find this if this ever happened to you.
So I migrated the site from cpanel to a new self managed server. (runcloud "on top off" digital ocean)
But after the migration it shows this kind of output.
Thanks for taking your time to answer this question.
I already searched for the same question but I don't seem to find the same problem.
`flush_rules(); //regestering menu register_nav_menus(array( 'top_menu'=>'Top navigation' ,'main_menu' => 'Main navigation' ,'inner_menu' => 'Inner navigation')); //add thumnails support if (function_exists('add_theme_support')){ add_theme_support('post-thumbnails'); } //disable auto image link function setup_default_image_link() { $original_setting = get_option( 'image_default_link'); if ($original_setting !== 'none') { update_option('image_default_link_type', 'none'); } } add_action('admin_init', 'setup_default_image_link', 50); update_option('image_default_link_type', 'none'); //remove P around images function filter_ptags_on_images($content){ return preg_replace('/
\s*()?\s*()\s*(<\/a>)?\s*<\/p>/iU', '\1\2\3', $content); } add_filter('the_content', 'filter_ptags_on_images'); //add support of page attributes add_post_type_support( 'post', 'page-attributes' ); /* * Switch default core markup for search form, comment form, and comments * to output valid HTML5. */ add_theme_support( 'html5', array( 'search-form', 'comment-form', 'comment-list', 'gallery', 'caption' ) ); //add custom header with image or video /* //image add_theme_support( 'custom-header' ); //video add_theme_support( 'custom-header', array( 'video' => true, ) ); /**/ //add_theme_support( 'selective-refresh' ); add_theme_support( 'customize-selective-refresh-widgets' ); /* auto-detect the server so you only have to enter the front/from half of the email address, including the # sign */ /** function xyz_filter_wp_mail_from($email){ $sitename = strtolower( $_SERVER['SERVER_NAME'] ); if ( substr( $sitename, 0, 4 ) == 'www.' ) { $sitename = substr( $sitename, 4 ); } $myfront = "noreply#"; $myback = $sitename; $myfrom = $myfront . $myback; return $myfrom; } add_filter("wp_mail_from", "xyz_filter_wp_mail_from"); function xyz_filter_wp_mail_from_name($from_name){ $sitename = strtolower( $_SERVER['SERVER_NAME'] ); if ( substr( $sitename, 0, 4 ) == 'www.' ) { $sitename = substr( $sitename, 4 ); } return $sitename; } add_filter("wp_mail_from_name", "xyz_filter_wp_mail_from_name"); /**/ //remove footer add_filter( 'admin_footer_text', '__return_empty_string', 11 ); add_filter( 'update_footer', '__return_empty_string', 11 ); //remove Category, Archive, etc. from title add_filter( 'get_the_archive_title', function ($title) { if ( is_category() ) { $title = sprintf( __( '%s' ), single_cat_title( '', false ) ); } elseif ( is_tag() ) { $title = sprintf( __( '%s' ), single_tag_title( '', false ) ); } elseif ( is_author() ) { $title = sprintf( __( '%s' ), '' . get_the_author() . '' ); } elseif ( is_year() ) { $title = sprintf( __( '%s' ), get_the_date( _x( 'Y', 'yearly archives date format' ) ) ); } elseif ( is_month() ) { $title = sprintf( __( '%s' ), get_the_date( _x( 'F Y', 'monthly archives date format' ) ) ); } elseif ( is_day() ) { $title = sprintf( __( '%s' ), get_the_date( _x( 'F j, Y', 'daily archives date format' ) ) ); } elseif ( is_tax( 'post_format' ) ) { if ( is_tax( 'post_format', 'post-format-aside' ) ) { $title = _x( '', 'post format archive title' ); } elseif ( is_tax( 'post_format', 'post-format-gallery' ) ) { $title = _x( '', 'post format archive title' ); } elseif ( is_tax( 'post_format', 'post-format-image' ) ) { $title = _x( '', 'post format archive title' ); } elseif ( is_tax( 'post_format', 'post-format-video' ) ) { $title = _x( '', 'post format archive title' ); } elseif ( is_tax( 'post_format', 'post-format-quote' ) ) { $title = _x( '', 'post format archive title' ); } elseif ( is_tax( 'post_format', 'post-format-link' ) ) { $title = _x( '', 'post format archive title' ); } elseif ( is_tax( 'post_format', 'post-format-status' ) ) { $title = _x( '', 'post format archive title' ); } elseif ( is_tax( 'post_format', 'post-format-audio' ) ) { $title = _x( '', 'post format archive title' ); } elseif ( is_tax( 'post_format', 'post-format-chat' ) ) { $title = _x( '', 'post format archive title' ); } } elseif ( is_post_type_archive() ) { $title = sprintf( __( '%s' ), post_type_archive_title( '', false ) ); } elseif ( is_tax() ) { $tax = get_taxonomy( get_queried_object()->taxonomy ); $title = sprintf( __( '%1$s: %2$s' ), $tax->labels->singular_name, single_term_title( '', false ) ); } else { $title = __( '' ); } return $title; }); //set count of posts on custom archive page function set_posts_per_page_for_towns_cpt( $query ) { if ( !is_admin() && $query->is_main_query() && is_post_type_archive( 'news' ) || is_tax( 'news_categories' ) ) { $query->set( 'posts_per_page', '6' ); }elseif ( !is_admin() && $query->is_main_query() && is_post_type_archive( 'our_work' ) ) { $query->set( 'posts_per_page', '6' ); } } add_action( 'pre_get_posts', 'set_posts_per_page_for_towns_cpt' ); function remove_menus(){ remove_menu_page( 'edit.php' ); //Posts http://sw/wp-admin/ // remove_menu_page( 'index.php' ); //Dashboard // remove_menu_page( 'jetpack' ); //Jetpack* // remove_menu_page( 'upload.php' ); //Media // remove_menu_page( 'edit.php?post_type=page' ); //Pages // remove_menu_page( 'edit-comments.php' ); //Comments // remove_menu_page( 'themes.php' ); //Appearance // remove_menu_page( 'plugins.php' ); //Plugins // remove_menu_page( 'users.php' ); //Users // remove_menu_page( 'tools.php' ); //Tools // remove_menu_page( 'options-general.php' ); //Settings } add_action( 'admin_menu', 'remove_menus' ); //add tiny mce templates add_filter( 'tinymce_templates_enable_media_buttons', function(){ return true; }); function change_wp_search_size($query) { if ( $query->is_search){ // Make sure it is a search page $query->query_vars['posts_per_page'] = -1; // Change 10 to the number of posts you would like to show //$query->set('post_type',array('publications')); } return $query; // Return our modified query variables } //add_filter('pre_get_posts', 'change_wp_search_size'); ?> array( 'name' => 'News', 'all_items' => 'All News' ), 'public' => true, 'has_archive' => true, 'rewrite' => array('slug' => 'news'), 'supports' => array('title'), 'exclude_from_search' => false )); register_post_type('events', array( 'labels' => array( 'name' => 'Events', 'all_items' => 'All Events' ), 'public' => true, 'has_archive' => true, 'rewrite' => array('slug' => 'events'), 'supports' => array('title'), 'exclude_from_search' => false )); register_post_type('publications', array( 'labels' => array( 'name' => 'Publications', 'all_items' => 'All Publications' ), 'public' => true, 'has_archive' => true, 'rewrite' => array('slug' => 'publications'), 'supports' => array('title'), 'exclude_from_search' => false )); register_post_type('our_work', array( 'labels' => array( 'name' => 'Our Work', 'all_items' => 'All Work' ), 'public' => true, 'has_archive' => true, 'rewrite' => array('slug' => 'our-work'), 'supports' => array('title'), 'exclude_from_search' => false )); register_post_type('members', array( 'labels' => array( 'name' => 'Our Members', 'all_items' => 'All Members' ), 'public' => true, 'has_archive' => true, 'rewrite' => array('slug' => 'members'), 'supports' => array('title'), 'exclude_from_search' => false )); } add_action('init', 'create_post_types'); // register Taxonomies function create_taxonomies() { register_taxonomy('news_categories', array('news'), array( 'labels' => array( 'name' => 'News Categories' ), 'show_ui' => true, 'show_tagcloud' => false, 'hierarchical' => true, 'rewrite' => array( 'slug' => 'news' ) )); register_taxonomy('publications_categories', array('publications'), array( 'labels' => array( 'name' => 'Publications Categories' ), 'show_ui' => true, 'show_tagcloud' => false, 'hierarchical' => true, 'rewrite' => array( 'slug' => 'publications' ) )); register_taxonomy('members_categories', array('members'), array( 'labels' => array( 'name' => 'Members Categories' ), 'show_ui' => true, 'show_tagcloud' => false, 'hierarchical' => true, 'rewrite' => array( 'slug' => 'members' ) )); } add_action('init', 'create_taxonomies'); // rewrite urls function taxonomy_slug_rewrite($wp_rewrite) { $rules = array(); $taxonomies = get_taxonomies(array('_builtin' => false), 'objects'); $post_types = get_post_types(array('public' => true, '_builtin' => false), 'names'); foreach ($post_types as $post_type) { foreach ($taxonomies as $taxonomy) { if ($taxonomy->object_type[0] == $post_type) { $categories = get_categories(array('type' => $post_type, 'taxonomy' => $taxonomy->name, 'hide_empty' => 0)); foreach ($categories as $category) { $rules[$post_type . '/' . $category->slug . '/?$'] = 'index.php?' . $category->taxonomy . '=' . $category->slug; } } } } $wp_rewrite->rules = $rules + $wp_rewrite->rules; } add_filter( 'generate_rewrite_rules', 'taxonomy_slug_rewrite' ); ?> $user_id, 'admin_color' => 'custom' ); wp_update_user( $args ); } add_action('user_register', 'set_default_admin_color'); if(get_current_user_id() != 1){ remove_action( 'admin_color_scheme_picker', 'admin_color_scheme_picker' ); } ?> admin_url( 'admin-ajax.php' ), 'nonce' => wp_create_nonce('myajax-nonce'))); //wp_localize_script('plugins', 'WPURLS', array( 'siteurl' => get_bloginfo("template_url") )); //wp_register_script( 'retina', get_template_directory_uri() . '/assets/js/libs/retina.min.js', array( 'backbone' )); wp_enqueue_script( 'custom-script' ); wp_enqueue_script('detect'); wp_enqueue_script('main_scripts'); wp_enqueue_script('plugins'); // wp_enqueue_script('retina'); } add_action( 'wp_enqueue_scripts', 'wptuts_scripts_with_jquery' ); //load admin scripts add_action( 'admin_enqueue_scripts', 'load_admin_scripts' ); function load_admin_scripts() { wp_enqueue_script( 'admin_js', get_admin_url() . 'backend/current/js/scripts.js' ); wp_localize_script( 'admin_js', 'backend_path', get_admin_url()); } if (!is_admin()) { //move all scripts to the footer function footer_enqueue_scripts(){ remove_action('wp_head','wp_print_scripts'); remove_action('wp_head','wp_print_head_scripts',9); remove_action('wp_head','wp_enqueue_scripts',1); add_action('wp_footer','wp_print_scripts',5); add_action('wp_footer','wp_enqueue_scripts',5); add_action('wp_footer','wp_print_head_scripts',5); } add_action('after_setup_theme','footer_enqueue_scripts'); } ?> __( 'Footer Main Menu', 'CURRENT WEBSITE' ), // 'id' => 'main_menu_widget', // 'description' => __( '', 'CURRENT WEBSITE' ), // 'before_widget' => '', // 'before_title' => '
', // 'after_title' => '
', // 'after_widget' => '
', // ) ); register_sidebar( array( 'name' => __( 'Facebook', 'CURRENT WEBSITE' ), 'id' => 'facebook_widget', 'description' => __( '', 'CURRENT WEBSITE' ), 'before_widget' => '
', 'before_title' => '
', 'after_title' => '
', 'after_widget' => '
', ) ); register_sidebar( array( 'name' => __( 'Twitter', 'CURRENT WEBSITE' ), 'id' => 'twitter_widget', 'description' => __( '', 'CURRENT WEBSITE' ), 'before_widget' => '', 'before_title' => '
', 'after_title' => '
', 'after_widget' => '
', ) ); register_sidebar( array( 'name' => __( 'Main Section Footer', 'CURRENT WEBSITE' ), 'id' => 'main_section_footer', 'description' => __( '', 'CURRENT WEBSITE' ), 'before_widget' => '
', 'after_widget' => '
', 'before_title' => '
', 'after_title' => '
', ) ); /* register_sidebar( array( 'name' => __( 'Language Switcher', 'CURRENT WEBSITE' ), 'id' => 'language_switcher', 'description' => __( '', 'CURRENT WEBSITE' ), 'before_widget' => '
', 'after_widget' => '
', 'before_title' => '
', 'after_title' => '
', ) ); register_sidebar( array( 'name' => __( 'Main Content Right Sidebar', 'CURRENT WEBSITE' ), 'id' => 'main_content_right_sidebar', 'description' => __( '', 'CURRENT WEBSITE' ), 'before_widget' => '
', 'after_widget' => '
', 'before_title' => '
', 'after_title' => '
', ) ); register_sidebar( array( 'name' => __( 'Main Content Left Sidebar', 'CURRENT WEBSITE' ), 'id' => 'main_content_left_sidebar', 'description' => __( '', 'CURRENT WEBSITE' ), 'before_widget' => '
', 'after_widget' => '
', 'before_title' => '
', 'after_title' => '
', ) ); register_sidebar( array( 'name' => __( 'Footer Right Sidebar', 'CURRENT WEBSITE' ), 'id' => 'footer_right_sidebar', 'description' => __( '', 'CURRENT WEBSITE' ), 'before_widget' => '
', 'after_widget' => '
', 'before_title' => '
', 'after_title' => '
', ) ); register_sidebar( array( 'name' => __( 'Footer Center Content', 'CURRENT WEBSITE' ), 'id' => 'footer_center_content', 'description' => __( '', 'CURRENT WEBSITE' ), 'before_widget' => '
', 'after_widget' => '
', 'before_title' => '
', 'after_title' => '
', ) ); */ } add_action( 'widgets_init', 'my_widgets_init' ); ?>`

Answer 1

If I understood the question correctly, you have some errors in your code but you don't know where exactly those errors are.
In this case you should either:
check your system PHP error log
or turn on WP_DEBUG in your wp-config.php file (see WP docs)
You'll see errors/warnings/notices produced by the PHP engine, and those messages will contain something like ... on line XXX in /some/path/to/some/file.php. This tells you exactly where the error/warning/notice happens. Open that file on that line and fix the issue.