From c778b6f0cf3de7fb3c6caa484cc223f0dceedd73 Mon Sep 17 00:00:00 2001
From: onli <onli@paskuda.biz>
Date: Sat, 27 Nov 2021 21:07:11 +0100
Subject: [PATCH] freetag 3.70.4: Prevent illegal offset error See
 https://board.s9y.org/viewtopic.php?f=10&t=25398

---
 serendipity_event_freetag/ChangeLog                     | 2 ++
 serendipity_event_freetag/serendipity_event_freetag.php | 8 ++++++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/serendipity_event_freetag/ChangeLog b/serendipity_event_freetag/ChangeLog
index 0859b6df..df19b8e9 100644
--- a/serendipity_event_freetag/ChangeLog
+++ b/serendipity_event_freetag/ChangeLog
@@ -1,3 +1,5 @@
+3.70.4: Fix a situation when an illegal offset error could occur
+
 3.70.3: Hotfixes for PHP 8 (surrim)
 
 3.70.2: Fix warning in RSS feed when using PHP 8
diff --git a/serendipity_event_freetag/serendipity_event_freetag.php b/serendipity_event_freetag/serendipity_event_freetag.php
index fbf55e4f..67318d2f 100644
--- a/serendipity_event_freetag/serendipity_event_freetag.php
+++ b/serendipity_event_freetag/serendipity_event_freetag.php
@@ -66,7 +66,7 @@ class serendipity_event_freetag extends serendipity_event
             'smarty'      => '2.6.7',
             'php'         => '7.0'
         ));
-        $propbag->add('version',       '3.70.3');
+        $propbag->add('version',       '3.70.4');
         $propbag->add('event_hooks',    array(
             'frontend_fetchentries'                             => true,
             'frontend_fetchentry'                               => true,
@@ -1548,7 +1548,11 @@ addLoadEvent(enableAutocomplete);
                 }
             }
         }
-        unset($tags[$tag]);
+        // Check that $tag is a valid value to prevent the 'illegal offset error' that will occur
+        // on real traffic patterns (unclear on which page exactly)
+        if ($tag != null && is_string($tag) && isset($tags[$tag])) {
+            unset($tags[$tag]);
+        }
         return $tags;
     }