Index: src/wp-includes/post-template.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- src/wp-includes/post-template.php	(revision a82a0df5f93ed7e8e8da9a150c2670b8d57153e8)
+++ src/wp-includes/post-template.php	(revision )
@@ -220,6 +220,8 @@
 	 */
 	$content = apply_filters( 'the_content', $content );
 	$content = str_replace( ']]>', ']]&gt;', $content );
+    /** Add &nbsp; before last word to prevent widow */
+    $content = preg_replace('/\s([\w]+[.,!\:;\\"-?]{0,1})$/', '&nbsp;\\1', $content);
 	echo $content;
 }