Index: wp-content/themes/twentysixteen/css/editor-style.css
===================================================================
--- wp-content/themes/twentysixteen/css/editor-style.css	(revision 54300)
+++ wp-content/themes/twentysixteen/css/editor-style.css	(working copy)
@@ -323,7 +323,7 @@
 table td,
 .mce-item-table td {
 	border-width: 0 1px 1px 0;
-	font-size: 16px;
+	font-size: inherit;
 	padding: 7px;
 	vertical-align: baseline;
 }