Index: vendor/magento/module-sales/Block/Adminhtml/Items/AbstractItems.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- src/vendor/magento/module-sales/Block/Adminhtml/Items/AbstractItems.php	(date 1567588428000)
+++ src/vendor/magento/module-sales/Block/Adminhtml/Items/AbstractItems.php	(date 1567588442526)
@@ -85,7 +85,7 @@
     {
         foreach ($blocks as $blockName) {
             $block = $this->getLayout()->getBlock($blockName);
-            if ($block->getRenderedBlock() === null) {
+            if ($block && $block->getRenderedBlock() === null) {
                 $block->setRenderedBlock($this);
             }
             $this->_columnRenders[$blockName] = $block;