diff --git a/program/steps/mail/compose.inc b/program/steps/mail/compose.inc
index f3ff19d72..b56f5b5b4 100644
--- a/program/steps/mail/compose.inc
+++ b/program/steps/mail/compose.inc
@@ -148,6 +148,9 @@ if ($font && !is_array($font)) {
   $OUTPUT->set_env('default_font', $font);
 }
 
+// default font size for HTML editor
+$OUTPUT->set_env('default_font_size', $RCMAIL->config->get('default_font_size'));
+
 // get reference message and set compose mode
 if ($msg_uid = $COMPOSE['param']['draft_uid']) {
   $compose_mode = RCUBE_COMPOSE_DRAFT;