diff --git a/.github/workflows/unittest.yml b/.github/workflows/unittest.yml
index 37fe359..ec99d47 100644
--- a/.github/workflows/unittest.yml
+++ b/.github/workflows/unittest.yml
@@ -11,7 +11,7 @@ jobs:
 
     strategy:
       matrix:
-        php-version: [8.0, 8.1, 8.2, 8.3, 8.4]
+        php-version: [8.0, 8.1, 8.2, 8.3, 8.4, 8.5]
 
     name: PHP ${{ matrix.php-version }} tests
     steps:
diff --git a/src/HostByBelle/CompressionBuffer.php b/src/HostByBelle/CompressionBuffer.php
index 16c9532..1a8d7af 100644
--- a/src/HostByBelle/CompressionBuffer.php
+++ b/src/HostByBelle/CompressionBuffer.php
@@ -120,9 +120,6 @@ public static function handler(string $buffer, int $phase = PHP_OUTPUT_HANDLER_F
                     }
                 }
             }
-
-            // We will return the original uncompressed content next, so tag the encoding as "identity"
-            self::sendHeader('Content-Encoding', 'identity');
         }
 
         return $buffer;
@@ -215,6 +212,11 @@ private static function doCompression(string $encoding, string $buffer): string
      */
     private static function sendHeader(string $name, string|int $value): void
     {
+        // We actually don't want to send a `Content-Encoding` header if the content isn't encoded as this behavior risks confusing the client.
+        if ($name === 'Content-Encoding' && $value === 'identity') {
+            return;
+        }
+
         if (is_callable(self::$headerHandler)) {
             call_user_func(self::$headerHandler, $name, $value);
         } else {