Index: src/wp-content/themes/twentyseventeen/style.css
===================================================================
--- src/wp-content/themes/twentyseventeen/style.css	(revision 38871)
+++ src/wp-content/themes/twentyseventeen/style.css	(working copy)
@@ -259,7 +259,7 @@
 }
 
 [type="search"] {
-	-webkit-appearance: textfield;
+	-webkit-appearance: none;
 	outline-offset: -2px;
 }