fix depr null on str_replace

functions.php

@@ -233,8 +233,8 @@ function gwp24_remove_adminbar( $wp_admin_bar ) {
   $wp_admin_bar->remove_node( 'view-site' );
 }
 
-add_filter( 'gettext', 'gwp24_change_howdy_text', 10, 2 );
-function gwp24_change_howdy_text( $translation, $original ) {
+add_filter( 'gettext', 'gwp24_change_howdy', 10, 2 );
+function gwp24_change_howdy( $translation, $original ) {
   if( 'Howdy, %1$s' == $original )
     $translation = '%1$s';
   return $translation;