diff --git a/mods/butterflies/init.lua b/mods/butterflies/init.lua
index 3b57e1ff..7414f5ff 100644
--- a/mods/butterflies/init.lua
+++ b/mods/butterflies/init.lua
@@ -59,7 +59,7 @@ for i in ipairs (butter_list) do
 			minetest.get_node_timer(pos):start(30)
 		end,
 		on_rightclick = function(...)
-			return false
+			return nil
 		end,
 		on_punch = function(pos, ...)
 			minetest.remove_node(pos)
diff --git a/mods/fireflies/init.lua b/mods/fireflies/init.lua
index 3b1ac3ff..8b642f39 100644
--- a/mods/fireflies/init.lua
+++ b/mods/fireflies/init.lua
@@ -85,7 +85,7 @@ minetest.register_node("fireflies:hidden_firefly", {
 		minetest.get_node_timer(pos):start(30)
 	end,
 	on_rightclick = function(...)
-		return false
+		return nil
 	end,
 	on_punch = function(pos, ...)
 		minetest.remove_node(pos)