diff --git a/app/code/Magento/Catalog/Model/Product/Price/Validation/Result.php b/app/code/Magento/Catalog/Model/Product/Price/Validation/Result.php
index 3d4d9f607da48..40fe6a01e260c 100644
--- a/app/code/Magento/Catalog/Model/Product/Price/Validation/Result.php
+++ b/app/code/Magento/Catalog/Model/Product/Price/Validation/Result.php
@@ -83,6 +83,12 @@ public function getFailedItems()
             }
         }
 
+        /**
+         * Clear validation messages to prevent wrong validation for subsequent price update.
+         * Work around for backward compatible changes.
+         */
+        $this->failedItems = [];
+
         return $failedItems;
     }
 }
diff --git a/app/code/Magento/Catalog/etc/db_schema.xml b/app/code/Magento/Catalog/etc/db_schema.xml
index 1c97c920266df..a0aa48fb76b13 100644
--- a/app/code/Magento/Catalog/etc/db_schema.xml
+++ b/app/code/Magento/Catalog/etc/db_schema.xml
@@ -138,6 +138,11 @@
         <index referenceId="CATALOG_PRODUCT_ENTITY_INT_STORE_ID" indexType="btree">
             <column name="store_id"/>
         </index>
+        <index referenceId="CATALOG_PRODUCT_ENTITY_INT_ATTRIBUTE_ID_STORE_ID_VALUE" indexType="btree">
+            <column name="attribute_id"/>
+            <column name="store_id"/>
+            <column name="value"/>
+        </index>
     </table>
     <table name="catalog_product_entity_text" resource="default" engine="innodb"
            comment="Catalog Product Text Attribute Backend Table">
diff --git a/app/code/Magento/Catalog/etc/db_schema_whitelist.json b/app/code/Magento/Catalog/etc/db_schema_whitelist.json
index d4bd6927d4345..f4cda73c371d0 100644
--- a/app/code/Magento/Catalog/etc/db_schema_whitelist.json
+++ b/app/code/Magento/Catalog/etc/db_schema_whitelist.json
@@ -69,7 +69,8 @@
         },
         "index": {
             "CATALOG_PRODUCT_ENTITY_INT_ATTRIBUTE_ID": true,
-            "CATALOG_PRODUCT_ENTITY_INT_STORE_ID": true
+            "CATALOG_PRODUCT_ENTITY_INT_STORE_ID": true,
+            "CATALOG_PRODUCT_ENTITY_INT_ATTRIBUTE_ID_STORE_ID_VALUE": true
         },
         "constraint": {
             "PRIMARY": true,
diff --git a/app/code/Magento/Contact/view/frontend/templates/form.phtml b/app/code/Magento/Contact/view/frontend/templates/form.phtml
index d218e650657ac..eee9f742a59a4 100644
--- a/app/code/Magento/Contact/view/frontend/templates/form.phtml
+++ b/app/code/Magento/Contact/view/frontend/templates/form.phtml
@@ -4,6 +4,9 @@
  * See COPYING.txt for license details.
  */
 
+// phpcs:disable Magento2.Templates.ThisInTemplate
+// phpcs:disable Generic.Files.LineLength.TooLong
+
 /** @var \Magento\Contact\Block\ContactForm $block */
 /** @var \Magento\Contact\ViewModel\UserDataProvider $viewModel */
 
@@ -23,35 +26,35 @@ $viewModel = $block->getViewModel();
         <div class="field name required">
             <label class="label" for="name"><span><?= $block->escapeHtml(__('Name')) ?></span></label>
             <div class="control">
-                <input name="name" 
-                       id="name" 
-                       title="<?= $block->escapeHtmlAttr(__('Name')) ?>" 
-                       value="<?= $block->escapeHtmlAttr($viewModel->getUserName()) ?>" 
-                       class="input-text" 
-                       type="text" 
+                <input name="name"
+                       id="name"
+                       title="<?= $block->escapeHtmlAttr(__('Name')) ?>"
+                       value="<?= $block->escapeHtmlAttr($viewModel->getUserName()) ?>"
+                       class="input-text"
+                       type="text"
                        data-validate="{required:true}"/>
             </div>
         </div>
         <div class="field email required">
             <label class="label" for="email"><span><?= $block->escapeHtml(__('Email')) ?></span></label>
             <div class="control">
-                <input name="email" 
-                       id="email" 
-                       title="<?= $block->escapeHtmlAttr(__('Email')) ?>" 
-                       value="<?= $block->escapeHtmlAttr($viewModel->getUserEmail()) ?>" 
-                       class="input-text" 
-                       type="email" 
+                <input name="email"
+                       id="email"
+                       title="<?= $block->escapeHtmlAttr(__('Email')) ?>"
+                       value="<?= $block->escapeHtmlAttr($viewModel->getUserEmail()) ?>"
+                       class="input-text"
+                       type="email"
                        data-validate="{required:true, 'validate-email':true}"/>
             </div>
         </div>
         <div class="field telephone">
             <label class="label" for="telephone"><span><?= $block->escapeHtml(__('Phone Number')) ?></span></label>
             <div class="control">
-                <input name="telephone" 
-                       id="telephone" 
-                       title="<?= $block->escapeHtmlAttr(__('Phone Number')) ?>" 
-                       value="<?= $block->escapeHtmlAttr($viewModel->getUserTelephone()) ?>" 
-                       class="input-text" 
+                <input name="telephone"
+                       id="telephone"
+                       title="<?= $block->escapeHtmlAttr(__('Phone Number')) ?>"
+                       value="<?= $block->escapeHtmlAttr($viewModel->getUserTelephone()) ?>"
+                       class="input-text"
                        type="tel" />
             </div>
         </div>
@@ -60,12 +63,12 @@ $viewModel = $block->getViewModel();
                 <span><?= $block->escapeHtml(__('What’s on your mind?')) ?></span>
             </label>
             <div class="control">
-                <textarea name="comment" 
-                          id="comment" 
-                          title="<?= $block->escapeHtmlAttr(__('What’s on your mind?')) ?>" 
-                          class="input-text" 
-                          cols="5" 
-                          rows="3" 
+                <textarea name="comment"
+                          id="comment"
+                          title="<?= $block->escapeHtmlAttr(__('What’s on your mind?')) ?>"
+                          class="input-text"
+                          cols="5"
+                          rows="3"
                           data-validate="{required:true}"><?= $block->escapeHtml($viewModel->getUserComment()) ?>
                 </textarea>
             </div>
@@ -81,3 +84,12 @@ $viewModel = $block->getViewModel();
         </div>
     </div>
 </form>
+<script type="text/x-magento-init">
+    {
+        "*": {
+            "Magento_Customer/js/block-submit-on-send": {
+                "formId": "contact-form"
+            }
+        }
+    }
+</script>
diff --git a/app/code/Magento/Customer/view/frontend/templates/form/forgotpassword.phtml b/app/code/Magento/Customer/view/frontend/templates/form/forgotpassword.phtml
index be201afa8f66c..caa501d48da83 100644
--- a/app/code/Magento/Customer/view/frontend/templates/form/forgotpassword.phtml
+++ b/app/code/Magento/Customer/view/frontend/templates/form/forgotpassword.phtml
@@ -6,6 +6,8 @@
  * @var $block \Magento\Customer\Block\Account\Forgotpassword
  */
 
+// phpcs:disable Generic.Files.LineLength.TooLong
+
 /** @var \Magento\Customer\Block\Account\Forgotpassword $block */
 ?>
 <form class="form password forget"
@@ -32,3 +34,12 @@
         </div>
     </div>
 </form>
+<script type="text/x-magento-init">
+    {
+        "*": {
+            "Magento_Customer/js/block-submit-on-send": {
+                "formId": "form-validate"
+            }
+        }
+    }
+</script>
diff --git a/app/code/Magento/Customer/view/frontend/templates/form/login.phtml b/app/code/Magento/Customer/view/frontend/templates/form/login.phtml
index ef74b0062c023..a1d1a0260672a 100644
--- a/app/code/Magento/Customer/view/frontend/templates/form/login.phtml
+++ b/app/code/Magento/Customer/view/frontend/templates/form/login.phtml
@@ -4,6 +4,8 @@
  * See COPYING.txt for license details.
  */
 
+// phpcs:disable Generic.Files.LineLength.TooLong
+
 /** @var \Magento\Customer\Block\Form\Login $block */
 ?>
 <div class="block block-customer-login">
@@ -22,13 +24,22 @@
                 <div class="field email required">
                     <label class="label" for="email"><span><?= $block->escapeHtml(__('Email')) ?></span></label>
                     <div class="control">
-                        <input name="login[username]" value="<?= $block->escapeHtmlAttr($block->getUsername()) ?>" <?php if ($block->isAutocompleteDisabled()) : ?> autocomplete="off"<?php endif; ?> id="email" type="email" class="input-text" title="<?= $block->escapeHtmlAttr(__('Email')) ?>" data-mage-init='{"mage/trim-input":{}}' data-validate="{required:true, 'validate-email':true}">
+                        <input name="login[username]" value="<?= $block->escapeHtmlAttr($block->getUsername()) ?>"
+                            <?php if ($block->isAutocompleteDisabled()): ?> autocomplete="off"<?php endif; ?>
+                               id="email" type="email" class="input-text"
+                               title="<?= $block->escapeHtmlAttr(__('Email')) ?>"
+                               data-mage-init='{"mage/trim-input":{}}'
+                               data-validate="{required:true, 'validate-email':true}">
                     </div>
                 </div>
                 <div class="field password required">
                     <label for="pass" class="label"><span><?= $block->escapeHtml(__('Password')) ?></span></label>
                     <div class="control">
-                        <input name="login[password]" type="password" <?php if ($block->isAutocompleteDisabled()) : ?> autocomplete="off"<?php endif; ?> class="input-text" id="pass" title="<?= $block->escapeHtmlAttr(__('Password')) ?>" data-validate="{required:true}">
+                        <input name="login[password]" type="password"
+                            <?php if ($block->isAutocompleteDisabled()): ?> autocomplete="off"<?php endif; ?>
+                               class="input-text" id="pass"
+                               title="<?= $block->escapeHtmlAttr(__('Password')) ?>"
+                               data-validate="{required:true}">
                     </div>
                 </div>
                 <?= $block->getChildHtml('form_additional_info') ?>
@@ -41,3 +52,12 @@
     </div>
 </div>
 
+<script type="text/x-magento-init">
+    {
+        "*": {
+            "Magento_Customer/js/block-submit-on-send": {
+                "formId": "login-form"
+            }
+        }
+    }
+</script>
diff --git a/app/code/Magento/Customer/view/frontend/templates/form/register.phtml b/app/code/Magento/Customer/view/frontend/templates/form/register.phtml
index f7d10f6df1728..e84861b9b5cf6 100644
--- a/app/code/Magento/Customer/view/frontend/templates/form/register.phtml
+++ b/app/code/Magento/Customer/view/frontend/templates/form/register.phtml
@@ -301,13 +301,6 @@ require([
         ignore: ignore ? ':hidden:not(' + ignore + ')' : ':hidden'
     <?php endif ?>
     }).find('input:text').attr('autocomplete', 'off');
-    dataForm.submit(function () {
-        $(this).find(':submit').attr('disabled', 'disabled');
-    });
-    dataForm.bind("invalid-form.validate", function () {
-        $(this).find(':submit').prop('disabled', false);
-    });
-
 });
 </script>
 <?php if ($block->getShowAddressFields()): ?>
@@ -337,6 +330,11 @@ require([
             "passwordStrengthIndicator": {
                 "formSelector": "form.form-create-account"
             }
+        },
+        "*": {
+            "Magento_Customer/js/block-submit-on-send": {
+                "formId": "form-validate"
+            }
         }
     }
 </script>
diff --git a/app/code/Magento/Customer/view/frontend/web/js/block-submit-on-send.js b/app/code/Magento/Customer/view/frontend/web/js/block-submit-on-send.js
new file mode 100644
index 0000000000000..b941ec7a254d8
--- /dev/null
+++ b/app/code/Magento/Customer/view/frontend/web/js/block-submit-on-send.js
@@ -0,0 +1,22 @@
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+define([
+    'jquery',
+    'mage/mage'
+], function ($) {
+    'use strict';
+
+    return function (config) {
+        var dataForm = $('#' + config.formId);
+
+        dataForm.submit(function () {
+            $(this).find(':submit').attr('disabled', 'disabled');
+        });
+        dataForm.bind('invalid-form.validate', function () {
+            $(this).find(':submit').prop('disabled', false);
+        });
+    };
+});
diff --git a/app/code/Magento/GoogleOptimizer/Observer/AbstractSave.php b/app/code/Magento/GoogleOptimizer/Observer/AbstractSave.php
index 135c8c92c6aa9..975788abe52e4 100644
--- a/app/code/Magento/GoogleOptimizer/Observer/AbstractSave.php
+++ b/app/code/Magento/GoogleOptimizer/Observer/AbstractSave.php
@@ -5,12 +5,16 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+declare(strict_types=1);
+
 namespace Magento\GoogleOptimizer\Observer;
 
 use Magento\Framework\Event\Observer;
 use Magento\Framework\Event\ObserverInterface;
 
 /**
+ * Abstract entity for saving codes
+ *
  * @api
  * @since 100.0.2
  */
@@ -96,7 +100,9 @@ protected function _processCode()
         $this->_initRequestParams();
 
         if ($this->_isNewCode()) {
-            $this->_saveCode();
+            if (!$this->_isEmptyCode()) {
+                $this->_saveCode();
+            }
         } else {
             $this->_loadCode();
             if ($this->_isEmptyCode()) {
@@ -185,6 +191,8 @@ protected function _deleteCode()
     }
 
     /**
+     * Check data availability
+     *
      * @return bool
      */
     private function isDataAvailable()
@@ -194,6 +202,8 @@ private function isDataAvailable()
     }
 
     /**
+     * Get request data
+     *
      * @return mixed
      */
     private function getRequestData()
diff --git a/app/code/Magento/GoogleOptimizer/Test/Unit/Observer/Product/SaveGoogleExperimentScriptObserverTest.php b/app/code/Magento/GoogleOptimizer/Test/Unit/Observer/Product/SaveGoogleExperimentScriptObserverTest.php
index 8a5c247369657..c6d02957c4be9 100644
--- a/app/code/Magento/GoogleOptimizer/Test/Unit/Observer/Product/SaveGoogleExperimentScriptObserverTest.php
+++ b/app/code/Magento/GoogleOptimizer/Test/Unit/Observer/Product/SaveGoogleExperimentScriptObserverTest.php
@@ -127,6 +127,39 @@ public function testCreatingCodeIfRequestIsValid()
         $this->_modelObserver->execute($this->_eventObserverMock);
     }
 
+    /**
+     * Test that code is not saving when request is empty
+     *
+     * @return void
+     */
+    public function testCreatingCodeIfRequestIsEmpty(): void
+    {
+        $this->_helperMock->expects(
+            $this->once()
+        )->method(
+            'isGoogleExperimentActive'
+        )->with(
+            $this->_storeId
+        )->willReturn(
+            true
+        );
+
+        $this->_requestMock->expects(
+            $this->exactly(3)
+        )->method(
+            'getParam'
+        )->with(
+            'google_experiment'
+        )->willReturn(
+            ['code_id' => '', 'experiment_script' => '']
+        );
+
+        $this->_codeMock->expects($this->never())->method('addData');
+        $this->_codeMock->expects($this->never())->method('save');
+
+        $this->_modelObserver->execute($this->_eventObserverMock);
+    }
+
     /**
      * @param array $params
      * @dataProvider dataProviderWrongRequestForCreating
diff --git a/app/code/Magento/Newsletter/view/frontend/templates/subscribe.phtml b/app/code/Magento/Newsletter/view/frontend/templates/subscribe.phtml
index 429482e5795bf..768c97ef316f7 100644
--- a/app/code/Magento/Newsletter/view/frontend/templates/subscribe.phtml
+++ b/app/code/Magento/Newsletter/view/frontend/templates/subscribe.phtml
@@ -40,3 +40,12 @@
         </form>
     </div>
 </div>
+<script type="text/x-magento-init">
+    {
+        "*": {
+            "Magento_Customer/js/block-submit-on-send": {
+                "formId": "newsletter-validate-detail"
+            }
+        }
+    }
+</script>
diff --git a/app/code/Magento/Quote/Model/Quote/Item/Processor.php b/app/code/Magento/Quote/Model/Quote/Item/Processor.php
index ef4b853862681..c6bef1cc80bfb 100644
--- a/app/code/Magento/Quote/Model/Quote/Item/Processor.php
+++ b/app/code/Magento/Quote/Model/Quote/Item/Processor.php
@@ -97,7 +97,9 @@ public function prepare(Item $item, DataObject $request, Product $candidate): vo
         $item->addQty($candidate->getCartQty());
 
         $customPrice = $request->getCustomPrice();
-        $item->setPrice($candidate->getFinalPrice());
+        if (!$item->getParentItem() || $item->getParentItem()->isChildrenCalculated()) {
+            $item->setPrice($candidate->getFinalPrice());
+        }
         if (!empty($customPrice)) {
             $item->setCustomPrice($customPrice);
             $item->setOriginalCustomPrice($customPrice);
diff --git a/app/code/Magento/Quote/Test/Unit/Model/Quote/Item/ProcessorTest.php b/app/code/Magento/Quote/Test/Unit/Model/Quote/Item/ProcessorTest.php
index cbcb7dd0adc3c..3025a72410671 100644
--- a/app/code/Magento/Quote/Test/Unit/Model/Quote/Item/ProcessorTest.php
+++ b/app/code/Magento/Quote/Test/Unit/Model/Quote/Item/ProcessorTest.php
@@ -77,7 +77,16 @@ protected function setUp(): void
 
         $this->itemMock = $this->getMockBuilder(Item::class)
             ->addMethods(['setOriginalCustomPrice'])
-            ->onlyMethods(['getId', 'setOptions', 'setProduct', 'addQty', 'setCustomPrice', 'setData', 'setPrice'])
+            ->onlyMethods([
+                'getId',
+                'setOptions',
+                'setProduct',
+                'addQty',
+                'setCustomPrice',
+                'setData',
+                'setPrice',
+                'getParentItem'
+            ])
             ->disableOriginalConstructor()
             ->getMock();
         $this->quoteItemFactoryMock->expects($this->any())
@@ -438,4 +447,41 @@ public function testPrepareWithResetCountAndNotStickAndSameItemId()
 
         $this->processor->prepare($this->itemMock, $this->objectMock, $this->productMock);
     }
+
+    /**
+     * @param bool $isChildrenCalculated
+     * @dataProvider prepareChildProductDataProvider
+     */
+    public function testPrepareChildProduct(bool $isChildrenCalculated): void
+    {
+        $finalPrice = 10;
+        $this->objectMock->method('getResetCount')
+            ->willReturn(false);
+        $this->productMock->method('getFinalPrice')
+            ->willReturn($finalPrice);
+        $this->itemMock->expects($isChildrenCalculated ? $this->once() : $this->never())
+            ->method('setPrice')
+            ->with($finalPrice)
+            ->willReturnSelf();
+        $parentItem = $this->createConfiguredMock(
+            \Magento\Quote\Model\Quote\Item::class,
+            [
+                'isChildrenCalculated' => $isChildrenCalculated
+            ]
+        );
+        $this->itemMock->method('getParentItem')
+            ->willReturn($parentItem);
+        $this->processor->prepare($this->itemMock, $this->objectMock, $this->productMock);
+    }
+
+    /**
+     * @return array
+     */
+    public function prepareChildProductDataProvider(): array
+    {
+        return [
+            [false],
+            [true]
+        ];
+    }
 }
diff --git a/app/code/Magento/SalesRule/view/frontend/requirejs-config.js b/app/code/Magento/SalesRule/view/frontend/requirejs-config.js
index 13b701c6fe65a..21f49fb3080fc 100644
--- a/app/code/Magento/SalesRule/view/frontend/requirejs-config.js
+++ b/app/code/Magento/SalesRule/view/frontend/requirejs-config.js
@@ -8,6 +8,9 @@ var config = {
         mixins: {
             'Magento_Checkout/js/action/select-payment-method': {
                 'Magento_SalesRule/js/action/select-payment-method-mixin': true
+            },
+            'Magento_Checkout/js/model/shipping-save-processor': {
+                'Magento_SalesRule/js/model/shipping-save-processor-mixin': true
             }
         }
     }
diff --git a/app/code/Magento/SalesRule/view/frontend/web/js/model/shipping-save-processor-mixin.js b/app/code/Magento/SalesRule/view/frontend/web/js/model/shipping-save-processor-mixin.js
new file mode 100644
index 0000000000000..193acb8eed2f4
--- /dev/null
+++ b/app/code/Magento/SalesRule/view/frontend/web/js/model/shipping-save-processor-mixin.js
@@ -0,0 +1,34 @@
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+define([
+    'mage/utils/wrapper',
+    'Magento_Checkout/js/model/quote',
+    'Magento_SalesRule/js/model/coupon'
+], function (wrapper, quote, coupon) {
+    'use strict';
+
+    return function (shippingSaveProcessor) {
+        shippingSaveProcessor.saveShippingInformation = wrapper.wrapSuper(
+            shippingSaveProcessor.saveShippingInformation,
+            function (type) {
+                var updateCouponCallback;
+
+                /**
+                 * Update coupon form
+                 */
+                updateCouponCallback = function () {
+                    if (quote.totals() && !quote.totals()['coupon_code']) {
+                        coupon.setCouponCode('');
+                        coupon.setIsApplied(false);
+                    }
+                };
+
+                return this._super(type).done(updateCouponCallback);
+            }
+        );
+
+        return shippingSaveProcessor;
+    };
+});
diff --git a/dev/tests/integration/testsuite/Magento/Catalog/Model/Product/Price/SpecialPriceStorageTest.php b/dev/tests/integration/testsuite/Magento/Catalog/Model/Product/Price/SpecialPriceStorageTest.php
new file mode 100644
index 0000000000000..0d8b0a825d24c
--- /dev/null
+++ b/dev/tests/integration/testsuite/Magento/Catalog/Model/Product/Price/SpecialPriceStorageTest.php
@@ -0,0 +1,69 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\Catalog\Model\Product\Price;
+
+use Magento\Catalog\Api\Data\SpecialPriceInterface;
+use Magento\Catalog\Api\Data\SpecialPriceInterfaceFactory;
+use Magento\TestFramework\Helper\Bootstrap;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Test special price storage model
+ */
+class SpecialPriceStorageTest extends TestCase
+{
+    /**
+     * @var SpecialPriceStorage
+     */
+    private $model;
+    /**
+     * @var SpecialPriceInterfaceFactory
+     */
+    private $specialPriceFactory;
+
+    /**
+     * @inheritDoc
+     */
+    protected function setUp(): void
+    {
+        parent::setUp();
+        $objectManager = Bootstrap::getObjectManager();
+        $this->model = $objectManager->get(SpecialPriceStorage::class);
+        $this->specialPriceFactory = $objectManager->get(SpecialPriceInterfaceFactory::class);
+    }
+
+    /**
+     * Test that price update validation works correctly
+     *
+     * @magentoDataFixture Magento/Catalog/_files/category_product.php
+     */
+    public function testUpdateValidationResult()
+    {
+        $date = new \Datetime('+2 days');
+        $date->setTime(0, 0);
+        /** @var SpecialPriceInterface $price */
+        $price = $this->specialPriceFactory->create();
+        $price->setSku('invalid')
+            ->setStoreId(0)
+            ->setPrice(5.0)
+            ->setPriceFrom($date->format('Y-m-d H:i:s'))
+            ->setPriceTo(
+                $date->modify('+1 day')
+                    ->format('Y-m-d H:i:s')
+            );
+        $result = $this->model->update([$price]);
+        $this->assertCount(1, $result);
+        $this->assertStringContainsString(
+            'The product that was requested doesn\'t exist.',
+            (string) $result[0]->getMessage()
+        );
+        $price->setSku('simple333');
+        $result = $this->model->update([$price]);
+        $this->assertCount(0, $result);
+    }
+}