From c9c23c6c4f77d0628126e2e839f477794cb8a59f Mon Sep 17 00:00:00 2001
From: Matias Griese <matias@trilbymedia.com>
Date: Wed, 23 Mar 2022 15:47:45 +0200
Subject: [PATCH] Better fix for `system.cache.gzip: true`

---
 CHANGELOG.md                                  |  2 +-
 .../src/Grav/Common/Errors/SystemFacade.php   | 21 +++++++++++++++++++
 system/src/Grav/Common/Grav.php               |  8 +++----
 3 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2a3590c4e..165516638 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,7 +12,7 @@
       - `text`, `url`, `hidden`, `commalist`: 2048
       - `text` (multiline), `textarea`: 65536
 3. [](#bugfix)
-   * Fixed issue with `system.cache.gzip: true` resulted in admin "Fetch Failed" for PHP 8.0+
+   * Fixed issue with `system.cache.gzip: true` resulted in admin "Fetch Failed" for PHP 8.0.17 and PHP 8.1.4 [PHP bug #8218](https://github.com/php/php-src/issues/8218).
    * Fix for multi-lang issues with Security Report
 
 # v1.7.31
diff --git a/system/src/Grav/Common/Errors/SystemFacade.php b/system/src/Grav/Common/Errors/SystemFacade.php
index edf2b5338..e13b0f6e7 100644
--- a/system/src/Grav/Common/Errors/SystemFacade.php
+++ b/system/src/Grav/Common/Errors/SystemFacade.php
@@ -43,4 +43,25 @@ class SystemFacade extends \Whoops\Util\SystemFacade
             $handler();
         }
     }
+
+
+    /**
+     * @param int $httpCode
+     *
+     * @return int
+     */
+    public function setHttpResponseCode($httpCode)
+    {
+        if (!headers_sent()) {
+            // Ensure that no 'location' header is present as otherwise this
+            // will override the HTTP code being set here, and mask the
+            // expected error page.
+            header_remove('location');
+
+            // Work around PHP bug #8218 (8.0.17 & 8.1.4).
+            header_remove('Content-Encoding');
+        }
+
+        return http_response_code($httpCode);
+    }
 }
diff --git a/system/src/Grav/Common/Grav.php b/system/src/Grav/Common/Grav.php
index 68a0bf3cf..7e3dcaff8 100644
--- a/system/src/Grav/Common/Grav.php
+++ b/system/src/Grav/Common/Grav.php
@@ -350,14 +350,12 @@ class Grav extends Container
      */
     public function cleanOutputBuffers(): void
     {
-        /** @var Config $config */
-        $config = $this['config'];
-        $gzip_enabled = (int) $config->get('system.cache.gzip');
-
         // Make sure nothing extra gets written to the response.
-        while (ob_get_level() > 2 + $gzip_enabled) {
+        while (ob_get_level()) {
             ob_end_clean();
         }
+        // Work around PHP bug #8218 (8.0.17 & 8.1.4).
+        header_remove('Content-Encoding');
     }
 
     /**