diff --git a/pxtblocks/plugins/newVariableField/fieldDropdownMixin.ts b/pxtblocks/plugins/newVariableField/fieldDropdownMixin.ts
index 0b91288da8b8..f329c1a4d43d 100644
--- a/pxtblocks/plugins/newVariableField/fieldDropdownMixin.ts
+++ b/pxtblocks/plugins/newVariableField/fieldDropdownMixin.ts
@@ -109,6 +109,10 @@ class HorizontalRuleMenuItem extends Blockly.MenuItem {
     getId(): string {
         return this.element_.id;
     }
+
+    isEnabled(): boolean {
+        return false;
+    }
 }
 
 Blockly.Css.register(`