Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function "wp_sitemaps_get_server" not found or invalid function name in /htdocs/wp-includes/class-wp-hook.php:324
Stack trace:
#0 /htdocs/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array)
#1 /htdocs/wp-includes/plugin.php(517): WP_Hook->do_action(Array)
#2 /htdocs/wp-settings.php(727): do_action('init')
#3 /htdocs/wp-config.php(98): require_once('/htdocs/wp-sett...')
#4 /htdocs/wp-load.php(50): require_once('/htdocs/wp-conf...')
#5 /htdocs/wp-blog-header.php(13): require_once('/htdocs/wp-load...')
#6 /htdocs/index.php(17): require('/htdocs/wp-blog...')
#7 {main}
thrown in /htdocs/wp-includes/class-wp-hook.php on line 324