diff --git a/app/code/Magento/Backend/App/AbstractAction.php b/app/code/Magento/Backend/App/AbstractAction.php
index ba90bc0c3e210..ffcbf3028b060 100644
--- a/app/code/Magento/Backend/App/AbstractAction.php
+++ b/app/code/Magento/Backend/App/AbstractAction.php
@@ -214,6 +214,7 @@ public function dispatch(\Magento\Framework\App\RequestInterface $request)
             $this->_view->loadLayout(['default', 'adminhtml_denied'], true, true, false);
             $this->_view->renderLayout();
             $this->_request->setDispatched(true);
+
             return $this->_response;
         }
 
@@ -223,6 +224,11 @@ public function dispatch(\Magento\Framework\App\RequestInterface $request)
 
         $this->_processLocaleSettings();
 
+        // Need to preload isFirstPageAfterLogin (see https://github.com/magento/magento2/issues/15510)
+        if ($this->_auth->isLoggedIn()) {
+            $this->_auth->getAuthStorage()->isFirstPageAfterLogin();
+        }
+
         return parent::dispatch($request);
     }
 
diff --git a/app/code/Magento/Catalog/view/frontend/web/js/catalog-add-to-cart.js b/app/code/Magento/Catalog/view/frontend/web/js/catalog-add-to-cart.js
index a819e4248fea7..3c969fc784bd5 100644
--- a/app/code/Magento/Catalog/view/frontend/web/js/catalog-add-to-cart.js
+++ b/app/code/Magento/Catalog/view/frontend/web/js/catalog-add-to-cart.js
@@ -33,6 +33,10 @@ define([
 
         _bindSubmit: function() {
             var self = this;
+            if (this.element.data('catalog-addtocart-initialized')) {
+                return;
+            }
+            this.element.data('catalog-addtocart-initialized', 1);
             this.element.on('submit', function(e) {
                 e.preventDefault();
                 self.submitForm($(this));
diff --git a/app/code/Magento/Customer/Controller/Section/Load.php b/app/code/Magento/Customer/Controller/Section/Load.php
index e99dcdb2cf96a..dbe640ef2a365 100644
--- a/app/code/Magento/Customer/Controller/Section/Load.php
+++ b/app/code/Magento/Customer/Controller/Section/Load.php
@@ -61,6 +61,8 @@ public function execute()
     {
         /** @var \Magento\Framework\Controller\Result\Json $resultJson */
         $resultJson = $this->resultJsonFactory->create();
+        $resultJson->setHeader('Cache-Control', 'max-age=0, must-revalidate, no-cache, no-store', true);
+        $resultJson->setHeader('Pragma', 'no-cache', true);
         try {
             $sectionNames = $this->getRequest()->getParam('sections');
             $sectionNames = $sectionNames ? array_unique(\explode(',', $sectionNames)) : null;
diff --git a/app/code/Magento/Ui/view/base/web/js/dynamic-rows/dynamic-rows-grid.js b/app/code/Magento/Ui/view/base/web/js/dynamic-rows/dynamic-rows-grid.js
index f9586981b4419..4cbb971073d79 100644
--- a/app/code/Magento/Ui/view/base/web/js/dynamic-rows/dynamic-rows-grid.js
+++ b/app/code/Magento/Ui/view/base/web/js/dynamic-rows/dynamic-rows-grid.js
@@ -104,9 +104,8 @@ define([
          * @param {String|Number} recordId
          */
         deleteRecord: function (index, recordId) {
-            this._super();
-
             this.updateInsertData(recordId);
+            this._super();
         },
 
         /**
diff --git a/app/code/Magento/Wishlist/Block/Rss/EmailLink.php b/app/code/Magento/Wishlist/Block/Rss/EmailLink.php
index fe0d3ba0f8c79..23b6a334e435f 100644
--- a/app/code/Magento/Wishlist/Block/Rss/EmailLink.php
+++ b/app/code/Magento/Wishlist/Block/Rss/EmailLink.php
@@ -22,7 +22,7 @@ class EmailLink extends Link
     protected $_template = 'rss/email.phtml';
 
     /**
-     * @return string
+     * @return array
      */
     protected function getLinkParams()
     {
diff --git a/app/code/Magento/Wishlist/Block/Rss/Link.php b/app/code/Magento/Wishlist/Block/Rss/Link.php
index f671cbd3cd6d6..2c9093669db7d 100644
--- a/app/code/Magento/Wishlist/Block/Rss/Link.php
+++ b/app/code/Magento/Wishlist/Block/Rss/Link.php
@@ -69,7 +69,7 @@ public function isRssAllowed()
     }
 
     /**
-     * @return string
+     * @return array
      */
     protected function getLinkParams()
     {
diff --git a/app/code/Magento/Wishlist/Helper/Data.php b/app/code/Magento/Wishlist/Helper/Data.php
index 469c4771646af..aff4894a7dee4 100644
--- a/app/code/Magento/Wishlist/Helper/Data.php
+++ b/app/code/Magento/Wishlist/Helper/Data.php
@@ -500,7 +500,7 @@ public function isAllowInCart()
     /**
      * Retrieve customer name
      *
-     * @return string|void
+     * @return string|null
      */
     public function getCustomerName()
     {
diff --git a/app/design/frontend/Magento/blank/web/css/source/_sections.less b/app/design/frontend/Magento/blank/web/css/source/_sections.less
index d5d6e5a3d105c..f0a3518c92a8b 100644
--- a/app/design/frontend/Magento/blank/web/css/source/_sections.less
+++ b/app/design/frontend/Magento/blank/web/css/source/_sections.less
@@ -20,9 +20,7 @@
 
 .media-width(@extremum, @break) when (@extremum = 'min') and (@break = @screen__m) {
     .product.data.items {
-        .lib-data-tabs(
-            @_tab-content-border-top-status: true
-        );
+        .lib-data-tabs();
     }
 }
 
diff --git a/app/design/frontend/Magento/blank/web/css/source/_variables.less b/app/design/frontend/Magento/blank/web/css/source/_variables.less
index 5d946dd8a826e..256bc796dba94 100644
--- a/app/design/frontend/Magento/blank/web/css/source/_variables.less
+++ b/app/design/frontend/Magento/blank/web/css/source/_variables.less
@@ -15,6 +15,16 @@
 @font-family-name__base: 'Open Sans';
 @font-family__base: @font-family-name__base, @font-family__sans-serif;
 
+//
+//  Sections variables
+//  _____________________________________________
+
+//
+//  Tabs
+//  ---------------------------------------------
+@tab-content__border-top-status: true;
+
+
 //
 //  Sidebar
 //  ---------------------------------------------
diff --git a/app/design/frontend/Magento/luma/web/css/source/_actions-toolbar.less b/app/design/frontend/Magento/luma/web/css/source/_actions-toolbar.less
index 096b93675a92c..d81d0a8388a78 100644
--- a/app/design/frontend/Magento/luma/web/css/source/_actions-toolbar.less
+++ b/app/design/frontend/Magento/luma/web/css/source/_actions-toolbar.less
@@ -22,10 +22,6 @@
                 &:last-child {
                     margin-bottom: 0;
                 }
-
-                &.primary {
-                    //  &:extend(.abs-button-l all);
-                }
             }
 
             &:last-child {
diff --git a/app/design/frontend/Magento/luma/web/css/source/_forms.less b/app/design/frontend/Magento/luma/web/css/source/_forms.less
index 7d8868bc104d7..65685b61a3b1f 100644
--- a/app/design/frontend/Magento/luma/web/css/source/_forms.less
+++ b/app/design/frontend/Magento/luma/web/css/source/_forms.less
@@ -91,11 +91,7 @@
     .select-styling() {
         .lib-css(appearance, none, 1);
         appearance: none;
-        background: @select__background url('../images/select-bg.svg') no-repeat 100% 45%;
         background-size: 30px 60px;
-        border: 1px solid @border-color__base;
-        height: 32px;
-        padding-right: 25px;
         text-indent: .01em;
         text-overflow: '';
 
diff --git a/app/design/frontend/Magento/luma/web/css/source/_theme.less b/app/design/frontend/Magento/luma/web/css/source/_theme.less
index 0ae3d757d01de..fc99d7ada8fa1 100644
--- a/app/design/frontend/Magento/luma/web/css/source/_theme.less
+++ b/app/design/frontend/Magento/luma/web/css/source/_theme.less
@@ -153,6 +153,13 @@
 //  Forms
 //  ---------------------------------------------
 
+
+//  Select
+@select__background: @form-element-input__background url('../images/select-bg.svg') no-repeat 100% 45%;
+@select__border: 1px solid @border-color__base;
+@select__height: 32px;
+@select__padding: 4px 25px @indent__xs @indent__s;
+
 //  Form fieldset
 @form-fieldset-legend__font-size: 18px;
 @form-fieldset-legend__font-weight: @font-weight__light;
diff --git a/dev/tests/static/framework/Magento/Sniffs/Less/PropertiesSortingSniff.php b/dev/tests/static/framework/Magento/Sniffs/Less/PropertiesSortingSniff.php
index 1f637e6b92876..963bb689a7921 100644
--- a/dev/tests/static/framework/Magento/Sniffs/Less/PropertiesSortingSniff.php
+++ b/dev/tests/static/framework/Magento/Sniffs/Less/PropertiesSortingSniff.php
@@ -101,7 +101,7 @@ public function process(PHP_CodeSniffer_File $phpcsFile, $stackPtr)
     private function validatePropertiesSorting(PHP_CodeSniffer_File $phpcsFile, $stackPtr, array $properties)
     {
         // Fix needed for cases when incorrect properties passed for validation due to bug in PHP tokens.
-        $symbolsForSkip = ['(', 'block'];
+        $symbolsForSkip = ['(', 'block', 'field'];
         $properties = array_filter(
             $properties,
             function ($var) use ($symbolsForSkip) {
diff --git a/lib/web/css/source/lib/variables/_forms.less b/lib/web/css/source/lib/variables/_forms.less
index 69d0146fb3555..fff6141c67fd5 100644
--- a/lib/web/css/source/lib/variables/_forms.less
+++ b/lib/web/css/source/lib/variables/_forms.less
@@ -121,7 +121,7 @@
 @select__disabled__font-style: @form-element-input__disabled__font-style;
 
 //  Focus state
-@select__focus__background: @form-element-input__focus__background;
+@select__focus__background: false;
 @select__focus__border: @form-element-input__focus__border;
 @select__focus__color: @form-element-input__focus__color;
 @select__focus__font-style: @form-element-input__focus__font-style;