diff --git a/lib/ace/css/editor.css b/lib/ace/css/editor.css
index 67b6522a..6be881fc 100644
--- a/lib/ace/css/editor.css
+++ b/lib/ace/css/editor.css
@@ -81,6 +81,7 @@
     opacity: 0;
     background: transparent;
     appearance: none;
+    -moz-appearance: none;
     border: none;
     resize: none;
     outline: none;