MC-1416: Editing Text Content Block from the Stage with TinyMCE 4 turned on

Add word-break: break-all to .magento-placeholder

Author: danmooney2

lib/web/mage/adminhtml/wysiwyg/tiny_mce/themes/ui.css

@@ -16,7 +16,7 @@
     font-size: 14px;
     color: #000;
     box-sizing: initial;
-    word-wrap: break-all;
+    word-break: break-all;
 }
 
 .magento-placeholder-error {