diff --git a/composer.lock b/composer.lock
index 25f0ade99fc..a66e0c7c0ae 100644
--- a/composer.lock
+++ b/composer.lock
@@ -1077,16 +1077,16 @@
         },
         {
             "name": "guzzlehttp/psr7",
-            "version": "1.8.3",
+            "version": "1.8.5",
             "source": {
                 "type": "git",
                 "url": "https://github.com/guzzle/psr7.git",
-                "reference": "1afdd860a2566ed3c2b0b4a3de6e23434a79ec85"
+                "reference": "337e3ad8e5716c15f9657bd214d16cc5e69df268"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/guzzle/psr7/zipball/1afdd860a2566ed3c2b0b4a3de6e23434a79ec85",
-                "reference": "1afdd860a2566ed3c2b0b4a3de6e23434a79ec85",
+                "url": "https://api.github.com/repos/guzzle/psr7/zipball/337e3ad8e5716c15f9657bd214d16cc5e69df268",
+                "reference": "337e3ad8e5716c15f9657bd214d16cc5e69df268",
                 "shasum": ""
             },
             "require": {
@@ -1111,12 +1111,12 @@
                 }
             },
             "autoload": {
-                "psr-4": {
-                    "GuzzleHttp\\Psr7\\": "src/"
-                },
                 "files": [
                     "src/functions_include.php"
-                ]
+                ],
+                "psr-4": {
+                    "GuzzleHttp\\Psr7\\": "src/"
+                }
             },
             "notification-url": "https://packagist.org/downloads/",
             "license": [
@@ -1167,7 +1167,7 @@
             ],
             "support": {
                 "issues": "https://github.com/guzzle/psr7/issues",
-                "source": "https://github.com/guzzle/psr7/tree/1.8.3"
+                "source": "https://github.com/guzzle/psr7/tree/1.8.5"
             },
             "funding": [
                 {
@@ -1183,7 +1183,7 @@
                     "type": "tidelift"
                 }
             ],
-            "time": "2021-10-05T13:56:00+00:00"
+            "time": "2022-03-20T21:51:18+00:00"
         },
         {
             "name": "laminas/laminas-diactoros",
diff --git a/composer/Metapackage/CoreRecommended/composer.json b/composer/Metapackage/CoreRecommended/composer.json
index af2291d7568..f342277e8ad 100644
--- a/composer/Metapackage/CoreRecommended/composer.json
+++ b/composer/Metapackage/CoreRecommended/composer.json
@@ -16,7 +16,7 @@
         "egulias/email-validator": "3.1.2",
         "guzzlehttp/guzzle": "6.5.5",
         "guzzlehttp/promises": "1.5.1",
-        "guzzlehttp/psr7": "1.8.3",
+        "guzzlehttp/psr7": "1.8.5",
         "laminas/laminas-diactoros": "2.8.0",
         "laminas/laminas-escaper": "2.9.0",
         "laminas/laminas-feed": "2.15.0",
diff --git a/core/lib/Drupal.php b/core/lib/Drupal.php
index cb763d58b4a..95a844288f6 100644
--- a/core/lib/Drupal.php
+++ b/core/lib/Drupal.php
@@ -75,7 +75,7 @@ class Drupal {
   /**
    * The current system version.
    */
-  const VERSION = '9.3.9-dev';
+  const VERSION = '9.3.10-dev';
 
   /**
    * Core API compatibility.