diff -r 48c4eec2b7e6 -r 8c2e4d02f4ef wp/wp-admin/network/site-users.php
--- a/wp/wp-admin/network/site-users.php	Fri Sep 05 18:40:08 2025 +0200
+++ b/wp/wp-admin/network/site-users.php	Fri Sep 05 18:52:52 2025 +0200
@@ -155,7 +155,7 @@
 					// If the user doesn't already belong to the blog, bail.
 					if ( ! is_user_member_of_blog( $user_id ) ) {
 						wp_die(
-							'<h1>' . __( 'Something went wrong.' ) . '</h1>' .
+							'<h1>' . __( 'An error occurred.' ) . '</h1>' .
 							'<p>' . __( 'One of the selected users is not a member of this site.' ) . '</p>',
 							403
 						);
@@ -341,6 +341,9 @@
 /**
  * Filters whether to show the Add New User form on the Multisite Users screen.
  *
+ * Note: While WordPress is moving towards simplifying labels by removing "New" from "Add New X" labels,
+ * we keep "Add New User" here to maintain a clear distinction from the "Add Existing User" section above.
+ *
  * @since 3.1.0
  *
  * @param bool $bool Whether to show the Add New User form. Default true.
@@ -374,7 +377,7 @@
 		</tr>
 	</table>
 	<?php wp_nonce_field( 'add-user', '_wpnonce_add-new-user' ); ?>
-	<?php submit_button( __( 'Add New User' ), 'primary', 'add-user', true, array( 'id' => 'submit-add-user' ) ); ?>
+	<?php submit_button( __( 'Add User' ), 'primary', 'add-user', true, array( 'id' => 'submit-add-user' ) ); ?>
 </form>
 <?php endif; ?>
 </div>