Index: src/wp-includes/js/wp-emoji.js
===================================================================
--- src/wp-includes/js/wp-emoji.js	(revision 32459)
+++ src/wp-includes/js/wp-emoji.js	(working copy)
@@ -70,11 +70,13 @@
 								node = node.parentNode;
 							}
 
-							if ( ! node || ( node.className && node.className.indexOf( 'wp-exclude-emoji' ) !== -1 ) ) {
+							if ( ! node || node.nodeType !== 1 || ( 'ownerSVGElement' in node ) ||
+								( node.className && typeof node.className === 'string' && node.className.indexOf( 'wp-exclude-emoji' ) !== -1 ) ) {
+
 								continue;
 							}
 
-							if ( node.nodeType === 1 && test( node.textContent ) ) {
+							if ( test( node.textContent ) ) {
 								parse( node );
 							}
 						}