diff --git a/R/collapse_rows.R b/R/collapse_rows.R
index af2c0a5..38a8216 100644
--- a/R/collapse_rows.R
+++ b/R/collapse_rows.R
@@ -66,6 +66,7 @@
 
   out <- as_kable_xml(kable_xml)
   attributes(out) <- kable_attrs
+  if (!"kableExtra" %in% class(out)) class(out) <- c("kableExtra", class(out))
   return(out)
 }