diff --git a/phpstan-baseline.php b/phpstan-baseline.php
index e775d6b9f5ef..5cf21e95d939 100644
--- a/phpstan-baseline.php
+++ b/phpstan-baseline.php
@@ -7543,12 +7543,6 @@
 	'count' => 1,
 	'path' => __DIR__ . '/system/Images/Handlers/BaseHandler.php',
 ];
-$ignoreErrors[] = [
-	// identifier: return.missing
-	'message' => '#^Method CodeIgniter\\\\Images\\\\Handlers\\\\BaseHandler\\:\\:__call\\(\\) should return mixed but return statement is missing\\.$#',
-	'count' => 1,
-	'path' => __DIR__ . '/system/Images/Handlers/BaseHandler.php',
-];
 $ignoreErrors[] = [
 	// identifier: missingType.iterableValue
 	'message' => '#^Method CodeIgniter\\\\Images\\\\Handlers\\\\BaseHandler\\:\\:_text\\(\\) has parameter \\$options with no value type specified in iterable type array\\.$#',
@@ -7699,12 +7693,6 @@
 	'count' => 1,
 	'path' => __DIR__ . '/system/Language/Language.php',
 ];
-$ignoreErrors[] = [
-	// identifier: missingType.iterableValue
-	'message' => '#^Method CodeIgniter\\\\Language\\\\Language\\:\\:load\\(\\) return type has no value type specified in iterable type array\\.$#',
-	'count' => 1,
-	'path' => __DIR__ . '/system/Language/Language.php',
-];
 $ignoreErrors[] = [
 	// identifier: missingType.iterableValue
 	'message' => '#^Method CodeIgniter\\\\Language\\\\Language\\:\\:parseLine\\(\\) return type has no value type specified in iterable type array\\.$#',
diff --git a/system/Filters/CSRF.php b/system/Filters/CSRF.php
index 6d90d6aee817..ea9a9939f2de 100644
--- a/system/Filters/CSRF.php
+++ b/system/Filters/CSRF.php
@@ -65,10 +65,9 @@ public function before(RequestInterface $request, $arguments = null)
      * We don't have anything to do here.
      *
      * @param list<string>|null $arguments
-     *
-     * @return void
      */
     public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
+        return null;
     }
 }
diff --git a/system/Filters/DebugToolbar.php b/system/Filters/DebugToolbar.php
index 9f864ee572c5..9e888ead35bb 100644
--- a/system/Filters/DebugToolbar.php
+++ b/system/Filters/DebugToolbar.php
@@ -30,6 +30,7 @@ class DebugToolbar implements FilterInterface
      */
     public function before(RequestInterface $request, $arguments = null)
     {
+        return null;
     }
 
     /**
@@ -41,5 +42,7 @@ public function before(RequestInterface $request, $arguments = null)
     public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
         service('toolbar')->prepare($request, $response);
+
+        return $response;
     }
 }
diff --git a/system/Filters/FilterInterface.php b/system/Filters/FilterInterface.php
index 0353fb2ab9d0..6df33e912b87 100644
--- a/system/Filters/FilterInterface.php
+++ b/system/Filters/FilterInterface.php
@@ -33,7 +33,7 @@ interface FilterInterface
      *
      * @param list<string>|null $arguments
      *
-     * @return RequestInterface|ResponseInterface|string|void
+     * @return RequestInterface|ResponseInterface|string|null
      */
     public function before(RequestInterface $request, $arguments = null);
 
@@ -45,7 +45,7 @@ public function before(RequestInterface $request, $arguments = null);
      *
      * @param list<string>|null $arguments
      *
-     * @return ResponseInterface|void
+     * @return ResponseInterface|null
      */
     public function after(RequestInterface $request, ResponseInterface $response, $arguments = null);
 }
diff --git a/system/Filters/ForceHTTPS.php b/system/Filters/ForceHTTPS.php
index 1a5bdc84349d..aa9cb3716d08 100644
--- a/system/Filters/ForceHTTPS.php
+++ b/system/Filters/ForceHTTPS.php
@@ -57,10 +57,9 @@ public function before(RequestInterface $request, $arguments = null)
      * We don't have anything to do here.
      *
      * @param array|null $arguments
-     *
-     * @return void
      */
     public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
+        return null;
     }
 }
diff --git a/system/Filters/Honeypot.php b/system/Filters/Honeypot.php
index cdff293aacb4..0a2745963595 100644
--- a/system/Filters/Honeypot.php
+++ b/system/Filters/Honeypot.php
@@ -36,12 +36,14 @@ class Honeypot implements FilterInterface
     public function before(RequestInterface $request, $arguments = null)
     {
         if (! $request instanceof IncomingRequest) {
-            return;
+            return null;
         }
 
         if (service('honeypot')->hasContent($request)) {
             throw HoneypotException::isBot();
         }
+
+        return null;
     }
 
     /**
@@ -52,5 +54,7 @@ public function before(RequestInterface $request, $arguments = null)
     public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
         service('honeypot')->attachHoneypot($response);
+
+        return $response;
     }
 }
diff --git a/system/Filters/InvalidChars.php b/system/Filters/InvalidChars.php
index 542b12d7ffbe..1cd775153c0e 100644
--- a/system/Filters/InvalidChars.php
+++ b/system/Filters/InvalidChars.php
@@ -48,13 +48,11 @@ class InvalidChars implements FilterInterface
      * Check invalid characters.
      *
      * @param list<string>|null $arguments
-     *
-     * @return void
      */
     public function before(RequestInterface $request, $arguments = null)
     {
         if (! $request instanceof IncomingRequest) {
-            return;
+            return null;
         }
 
         $data = [
@@ -69,17 +67,18 @@ public function before(RequestInterface $request, $arguments = null)
             $this->checkEncoding($values);
             $this->checkControl($values);
         }
+
+        return null;
     }
 
     /**
      * We don't have anything to do here.
      *
      * @param list<string>|null $arguments
-     *
-     * @return void
      */
     public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
+        return null;
     }
 
     /**
diff --git a/system/Filters/PageCache.php b/system/Filters/PageCache.php
index d4fb6ab24662..76a3faaaf7e1 100644
--- a/system/Filters/PageCache.php
+++ b/system/Filters/PageCache.php
@@ -59,8 +59,6 @@ public function before(RequestInterface $request, $arguments = null)
      * Cache the page.
      *
      * @param array|null $arguments
-     *
-     * @return void
      */
     public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
@@ -74,6 +72,9 @@ public function after(RequestInterface $request, ResponseInterface $response, $a
             // so that we can have live speed updates along the way.
             // Must be run after filters to preserve the Response headers.
             $this->pageCache->make($request, $response);
+            return $response;
         }
+
+        return null;
     }
 }
diff --git a/system/Filters/PerformanceMetrics.php b/system/Filters/PerformanceMetrics.php
index f2371c7a8d6d..0a9db2078500 100644
--- a/system/Filters/PerformanceMetrics.php
+++ b/system/Filters/PerformanceMetrics.php
@@ -28,14 +28,13 @@ class PerformanceMetrics implements FilterInterface
      */
     public function before(RequestInterface $request, $arguments = null)
     {
+        return null;
     }
 
     /**
      * Replaces the performance metrics.
      *
      * @param array|null $arguments
-     *
-     * @return void
      */
     public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
@@ -57,6 +56,10 @@ public function after(RequestInterface $request, ResponseInterface $response, $a
             );
 
             $response->setBody($output);
+
+            return $response;
         }
+
+        return null;
     }
 }
diff --git a/system/Filters/SecureHeaders.php b/system/Filters/SecureHeaders.php
index b8bd6e05f8eb..42e5842384db 100644
--- a/system/Filters/SecureHeaders.php
+++ b/system/Filters/SecureHeaders.php
@@ -52,24 +52,23 @@ class SecureHeaders implements FilterInterface
      * We don't have anything to do here.
      *
      * @param list<string>|null $arguments
-     *
-     * @return void
      */
     public function before(RequestInterface $request, $arguments = null)
     {
+        return null;
     }
 
     /**
      * Add security headers.
      *
      * @param list<string>|null $arguments
-     *
-     * @return void
      */
     public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
         foreach ($this->headers as $header => $value) {
             $response->setHeader($header, $value);
         }
+
+        return $response;
     }
 }
diff --git a/tests/_support/Filters/Customfilter.php b/tests/_support/Filters/Customfilter.php
index ac8bce0f0271..7cfb89f60d48 100644
--- a/tests/_support/Filters/Customfilter.php
+++ b/tests/_support/Filters/Customfilter.php
@@ -26,7 +26,8 @@ public function before(RequestInterface $request, $arguments = null)
         return $request;
     }
 
-    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null): void
+    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
+        return null;
     }
 }
diff --git a/tests/_support/Filters/RedirectFilter.php b/tests/_support/Filters/RedirectFilter.php
index 8ab62eb665ca..b2e9289d6b6b 100644
--- a/tests/_support/Filters/RedirectFilter.php
+++ b/tests/_support/Filters/RedirectFilter.php
@@ -24,7 +24,8 @@ public function before(RequestInterface $request, $arguments = null)
         return redirect()->to('login');
     }
 
-    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null): void
+    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
+        return null;
     }
 }
diff --git a/tests/system/Filters/fixtures/GoogleCurious.php b/tests/system/Filters/fixtures/GoogleCurious.php
index f00bc065f1d7..6a6871fcc8d4 100644
--- a/tests/system/Filters/fixtures/GoogleCurious.php
+++ b/tests/system/Filters/fixtures/GoogleCurious.php
@@ -24,7 +24,8 @@ public function before(RequestInterface $request, $arguments = null)
         return 'This is curious';
     }
 
-    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null): void
+    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
+        return null;
     }
 }
diff --git a/tests/system/Filters/fixtures/GoogleEmpty.php b/tests/system/Filters/fixtures/GoogleEmpty.php
index 6b0003e8de16..9de00d28f514 100644
--- a/tests/system/Filters/fixtures/GoogleEmpty.php
+++ b/tests/system/Filters/fixtures/GoogleEmpty.php
@@ -24,7 +24,8 @@ public function before(RequestInterface $request, $arguments = null)
         return '';
     }
 
-    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null): void
+    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
+        return null;
     }
 }
diff --git a/tests/system/Filters/fixtures/GoogleYou.php b/tests/system/Filters/fixtures/GoogleYou.php
index 7d2913866b30..5911940b2954 100644
--- a/tests/system/Filters/fixtures/GoogleYou.php
+++ b/tests/system/Filters/fixtures/GoogleYou.php
@@ -27,7 +27,8 @@ public function before(RequestInterface $request, $arguments = null)
         return $response;
     }
 
-    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null): void
+    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
+        return null;
     }
 }
diff --git a/tests/system/Filters/fixtures/Multiple1.php b/tests/system/Filters/fixtures/Multiple1.php
index e9f4f49a10ab..6d2cee231808 100644
--- a/tests/system/Filters/fixtures/Multiple1.php
+++ b/tests/system/Filters/fixtures/Multiple1.php
@@ -26,7 +26,8 @@ public function before(RequestInterface $request, $arguments = null)
         return $request;
     }
 
-    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null): void
+    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
+        return null;
     }
 }
diff --git a/tests/system/Filters/fixtures/Multiple2.php b/tests/system/Filters/fixtures/Multiple2.php
index 5520ce549930..d86f8fa79399 100644
--- a/tests/system/Filters/fixtures/Multiple2.php
+++ b/tests/system/Filters/fixtures/Multiple2.php
@@ -26,7 +26,8 @@ public function before(RequestInterface $request, $arguments = null)
         return $request;
     }
 
-    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null): void
+    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
     {
+        return null;
     }
 }