diff --git a/layout/media/symbols.def.in b/layout/media/symbols.def.in
index 71290aa120..3ce51f9b3b 100644
--- a/layout/media/symbols.def.in
+++ b/layout/media/symbols.def.in
@@ -76,6 +76,7 @@ dav1d_open
 dav1d_parse_sequence_header
 dav1d_send_data
 dav1d_get_picture
+dav1d_flush
 dav1d_close
 dav1d_data_create
 dav1d_data_unref