Index: src/wp-admin/css/site-icon.css
===================================================================
--- src/wp-admin/css/site-icon.css	(revision 37962)
+++ src/wp-admin/css/site-icon.css	(working copy)
@@ -36,8 +36,15 @@
 	overflow: hidden;
 	width: 64px;
 	margin-top: 5px;
+	direction: ltr;
 }
 
+/* rtl:ignore */
+.site-icon-preview .favicon,
+.site-icon-preview .app-icon-preview {
+	direction: ltr;
+}
+
 .customize-control-site_icon .favicon-preview {
 	float: left;
 	margin-right: 12px;