From dd676d76cfcea748fb62c5713cc0879d3c538afd Mon Sep 17 00:00:00 2001
From: Mike Little <mike@zed1.com>
Date: Mon, 18 May 2026 13:43:33 +0100
Subject: [PATCH]   Fix PHP 8.4+ implicit-nullable deprecation in U2F Error
 constructor

  Add explicit ?\Exception type to the $previous parameter. Implicit
  nullable parameters (Type $x = null) are deprecated as of PHP 8.4 and
  emit a deprecation notice on every class load under PHP 8.5.

  Matches the existing @param \Exception|null docblock.
---
 includes/Yubico/U2F.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/includes/Yubico/U2F.php b/includes/Yubico/U2F.php
index e819bbc1..bbb6e9a0 100644
--- a/includes/Yubico/U2F.php
+++ b/includes/Yubico/U2F.php
@@ -501,7 +501,7 @@ class Error extends \Exception
      * @param int $code
      * @param \Exception|null $previous
      */
-    public function __construct($message, $code, \Exception $previous = null) {
+    public function __construct($message, $code, ?\Exception $previous = null) {
         parent::__construct($message, $code, $previous);
     }
 }