Index: wp-content/themes/twentyfourteen/css/blocks.css
===================================================================
--- wp-content/themes/twentyfourteen/css/blocks.css	(revision 58682)
+++ wp-content/themes/twentyfourteen/css/blocks.css	(working copy)
@@ -357,6 +357,12 @@
 	font-size: 16px;
 }
 
+:root :where(ol.wp-block-latest-comments[class*="has-"][class$="-font-size"]) .wp-block-latest-comments__comment,
+:root :where(ol.wp-block-latest-comments[class*="has-"][class$="-font-size"]) .wp-block-latest-comments__comment-excerpt,
+:root :where(ol.wp-block-latest-comments[class*="has-"][class$="-font-size"]) .wp-block-latest-comments__comment-excerpt p{
+    font-size:inherit;
+}
+
 .wp-block-latest-comments__comment-meta a {
 	color: #2b2b2b;
 	font-weight: 900;