Index: src/wp-content/themes/twentyfifteen/style.css
===================================================================
--- src/wp-content/themes/twentyfifteen/style.css	(revision 33068)
+++ src/wp-content/themes/twentyfifteen/style.css	(working copy)
@@ -490,6 +490,10 @@
 
 button,
 input {
+	-webkit-hyphens: none;
+	-moz-hyphens: none;
+	-ms-hyphens: none;
+	hyphens: none;
 	line-height: normal;
 }