diff --git a/composer.lock b/composer.lock
index 93b8c29a8bf2f0224919d800b30f90c06573c99e..dd8d8dceedfd9feb5e023a6e6d91a2e6fe4de8a5 100644
--- a/composer.lock
+++ b/composer.lock
@@ -491,7 +491,7 @@
         },
         {
             "name": "drupal/core",
-            "version": "10.4.x-dev",
+            "version": "10.5.x-dev",
             "dist": {
                 "type": "path",
                 "url": "core",
@@ -652,7 +652,7 @@
         },
         {
             "name": "drupal/core-project-message",
-            "version": "10.4.x-dev",
+            "version": "10.5.x-dev",
             "dist": {
                 "type": "path",
                 "url": "composer/Plugin/ProjectMessage",
@@ -685,7 +685,7 @@
         },
         {
             "name": "drupal/core-vendor-hardening",
-            "version": "10.4.x-dev",
+            "version": "10.5.x-dev",
             "dist": {
                 "type": "path",
                 "url": "composer/Plugin/VendorHardening",
@@ -9623,8 +9623,8 @@
     },
     "prefer-stable": true,
     "prefer-lowest": false,
-    "platform": {},
-    "platform-dev": {},
+    "platform": [],
+    "platform-dev": [],
     "platform-overrides": {
         "php": "8.1.0"
     },
diff --git a/composer/Metapackage/CoreRecommended/composer.json b/composer/Metapackage/CoreRecommended/composer.json
index 37dee4f1b66fc8dd993ca1e65d3277e2b9eaceed..4cdd9b87c611050f57b0fb837a7fcfb4b2559384 100644
--- a/composer/Metapackage/CoreRecommended/composer.json
+++ b/composer/Metapackage/CoreRecommended/composer.json
@@ -7,7 +7,7 @@
         "webflo/drupal-core-strict": "*"
     },
     "require": {
-        "drupal/core": "10.4.x-dev",
+        "drupal/core": "10.5.x-dev",
         "asm89/stack-cors": "~v2.2.0",
         "composer/semver": "~3.4.3",
         "doctrine/annotations": "~1.14.3",
diff --git a/composer/Metapackage/PinnedDevDependencies/composer.json b/composer/Metapackage/PinnedDevDependencies/composer.json
index cfdb325fe8a63a0dd487b3df7bd204e6ce9bed65..2be30180cd0b6ff249a4979712e52575d33a8ba9 100644
--- a/composer/Metapackage/PinnedDevDependencies/composer.json
+++ b/composer/Metapackage/PinnedDevDependencies/composer.json
@@ -7,7 +7,7 @@
         "webflo/drupal-core-require-dev": "*"
     },
     "require": {
-        "drupal/core": "10.4.x-dev",
+        "drupal/core": "10.5.x-dev",
         "behat/mink": "v1.12.0",
         "behat/mink-browserkit-driver": "v2.2.0",
         "colinodell/psr-testlogger": "v1.3.0",
diff --git a/composer/Template/LegacyProject/composer.json b/composer/Template/LegacyProject/composer.json
index 508b5b36460ba34dc36052a0db6517a0c16e2ad8..056ae7e967c71020fe944be65280a4ec3adbc49f 100644
--- a/composer/Template/LegacyProject/composer.json
+++ b/composer/Template/LegacyProject/composer.json
@@ -16,13 +16,13 @@
     ],
     "require": {
         "composer/installers": "^2.0",
-        "drupal/core-composer-scaffold": "^10.4",
-        "drupal/core-project-message": "^10.4",
-        "drupal/core-recommended": "^10.4",
-        "drupal/core-vendor-hardening": "^10.4"
+        "drupal/core-composer-scaffold": "^10.5",
+        "drupal/core-project-message": "^10.5",
+        "drupal/core-recommended": "^10.5",
+        "drupal/core-vendor-hardening": "^10.5"
     },
     "require-dev": {
-        "drupal/core-dev": "^10.4"
+        "drupal/core-dev": "^10.5"
     },
     "conflict": {
         "drupal/drupal": "*"
diff --git a/composer/Template/RecommendedProject/composer.json b/composer/Template/RecommendedProject/composer.json
index 032ef9ff94b84c875c0008716ad8084ef11de994..809bc54cd7c995ce5d3df246fdb7174044ef483c 100644
--- a/composer/Template/RecommendedProject/composer.json
+++ b/composer/Template/RecommendedProject/composer.json
@@ -16,12 +16,12 @@
     ],
     "require": {
         "composer/installers": "^2.0",
-        "drupal/core-composer-scaffold": "^10.4",
-        "drupal/core-project-message": "^10.4",
-        "drupal/core-recommended": "^10.4"
+        "drupal/core-composer-scaffold": "^10.5",
+        "drupal/core-project-message": "^10.5",
+        "drupal/core-recommended": "^10.5"
     },
     "require-dev": {
-        "drupal/core-dev": "^10.4"
+        "drupal/core-dev": "^10.5"
     },
     "conflict": {
         "drupal/drupal": "*"
diff --git a/core/lib/Drupal.php b/core/lib/Drupal.php
index d5e9983bbd40b31afa797ceac847dda2c84ca5e0..ba8a323398f685a901bfcb3c1981d70cd3fdf27b 100644
--- a/core/lib/Drupal.php
+++ b/core/lib/Drupal.php
@@ -75,7 +75,7 @@ class Drupal {
   /**
    * The current system version.
    */
-  const VERSION = '10.4.0-dev';
+  const VERSION = '10.5.0-dev';
 
   /**
    * Core API compatibility.
diff --git a/core/lib/Drupal/Component/Annotation/composer.json b/core/lib/Drupal/Component/Annotation/composer.json
index 697c06f01097c40a0a171db297e6977a33edca55..155c4f63148caa4232b2ae9f3eb0e304bb20228e 100644
--- a/core/lib/Drupal/Component/Annotation/composer.json
+++ b/core/lib/Drupal/Component/Annotation/composer.json
@@ -9,10 +9,10 @@
     "require": {
         "php": ">=8.1.0",
         "doctrine/annotations": "^1.14",
-        "drupal/core-class-finder": "10.4.x-dev",
-        "drupal/core-file-cache": "10.4.x-dev",
-        "drupal/core-plugin": "10.4.x-dev",
-        "drupal/core-utility": "10.4.x-dev"
+        "drupal/core-class-finder": "10.5.x-dev",
+        "drupal/core-file-cache": "10.5.x-dev",
+        "drupal/core-plugin": "10.5.x-dev",
+        "drupal/core-utility": "10.5.x-dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/core/lib/Drupal/Component/Datetime/composer.json b/core/lib/Drupal/Component/Datetime/composer.json
index e35cc2cda1a2e2552d3c352f3b00b223ec9badba..717796344f369243dc4d88a3a243fd4a69d89541 100644
--- a/core/lib/Drupal/Component/Datetime/composer.json
+++ b/core/lib/Drupal/Component/Datetime/composer.json
@@ -8,7 +8,7 @@
     "license": "GPL-2.0-or-later",
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-utility": "10.4.x-dev"
+        "drupal/core-utility": "10.5.x-dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/core/lib/Drupal/Component/Discovery/composer.json b/core/lib/Drupal/Component/Discovery/composer.json
index 34d34067c175fc7c4888faad7679cb3d5eb02faa..74cc55e0ec3f1fbd82be49c56241dca551ed1856 100644
--- a/core/lib/Drupal/Component/Discovery/composer.json
+++ b/core/lib/Drupal/Component/Discovery/composer.json
@@ -8,8 +8,8 @@
     "license": "GPL-2.0-or-later",
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-file-cache": "10.4.x-dev",
-        "drupal/core-serialization": "10.4.x-dev"
+        "drupal/core-file-cache": "10.5.x-dev",
+        "drupal/core-serialization": "10.5.x-dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/core/lib/Drupal/Component/FrontMatter/composer.json b/core/lib/Drupal/Component/FrontMatter/composer.json
index 3ac47f3785b2550220f299a67ccdda5fe80cf914..a6e7972c26cd42a5a78bda82b44144960b4f7af1 100644
--- a/core/lib/Drupal/Component/FrontMatter/composer.json
+++ b/core/lib/Drupal/Component/FrontMatter/composer.json
@@ -8,7 +8,7 @@
     "license": "GPL-2.0-or-later",
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-serialization": "10.4.x-dev"
+        "drupal/core-serialization": "10.5.x-dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/core/lib/Drupal/Component/Gettext/composer.json b/core/lib/Drupal/Component/Gettext/composer.json
index 6b731b3c158a084cc2f05431fc7bc1e597b28b16..ab509cc8deb55e1e4c260db76bc80c7c204d4b8c 100644
--- a/core/lib/Drupal/Component/Gettext/composer.json
+++ b/core/lib/Drupal/Component/Gettext/composer.json
@@ -9,7 +9,7 @@
     },
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-render": "10.4.x-dev"
+        "drupal/core-render": "10.5.x-dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/core/lib/Drupal/Component/PhpStorage/composer.json b/core/lib/Drupal/Component/PhpStorage/composer.json
index 395e10d24350ab7a90fbe16855eda7de99e23b4d..d9d6b812545eab627780efc801b3f7e6887cebf1 100644
--- a/core/lib/Drupal/Component/PhpStorage/composer.json
+++ b/core/lib/Drupal/Component/PhpStorage/composer.json
@@ -8,7 +8,7 @@
     "license": "GPL-2.0-or-later",
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-file-security": "10.4.x-dev"
+        "drupal/core-file-security": "10.5.x-dev"
     },
     "autoload": {
         "psr-4": {
diff --git a/core/lib/Drupal/Component/Render/composer.json b/core/lib/Drupal/Component/Render/composer.json
index 72c0060d2669a2774b2e205768352a88bbe17ed3..0b83185193d391cf4a2e0a4b02daebf815e5b06d 100644
--- a/core/lib/Drupal/Component/Render/composer.json
+++ b/core/lib/Drupal/Component/Render/composer.json
@@ -8,7 +8,7 @@
     "license": "GPL-2.0-or-later",
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-utility": "10.4.x-dev"
+        "drupal/core-utility": "10.5.x-dev"
     },
     "autoload": {
         "psr-4": {