diff --git a/core/themes/bartik/templates/comment.html.twig b/core/themes/bartik/templates/comment.html.twig
index 2dac831..f7188a8 100644
--- a/core/themes/bartik/templates/comment.html.twig
+++ b/core/themes/bartik/templates/comment.html.twig
@@ -71,7 +71,7 @@
   set classes = [
     'comment',
     status != 'published' ? 'comment--' ~ status,
-    comment.owner.anonymous ? 'by-anonymous',
+    comment.getOwner().isAnonymous() ? 'by-anonymous',
     author_id and author_id == commented_entity.getOwnerId() ? 'by-' ~ commented_entity.getEntityTypeId() ~ '-author',
     'clearfix',
   ]
diff --git a/core/themes/classy/templates/content/comment.html.twig b/core/themes/classy/templates/content/comment.html.twig
index bb06364..bece7f3 100644
--- a/core/themes/classy/templates/content/comment.html.twig
+++ b/core/themes/classy/templates/content/comment.html.twig
@@ -71,7 +71,7 @@
   set classes = [
     'comment',
     status != 'published' ? status,
-    comment.owner.anonymous ? 'by-anonymous',
+    comment.getOwner().isAnonymous() ? 'by-anonymous',
     author_id and author_id == commented_entity.getOwnerId() ? 'by-' ~ commented_entity.getEntityTypeId() ~ '-author',
     'clearfix',
   ]