Fix fire extinguisher not being fillable with the top off.

code/game/objects/items/weapons/extinguisher.dm

@@ -82,7 +82,7 @@
 				flags &= ~OPENCONTAINER
 		return
 
-	if (istype(W, /obj/item))
+	if (istype(W, /obj/item) && !is_open_container())
 		if(W.w_class>1)
 			user << "\The [W] won't fit into the nozzle!"
 			return
@@ -212,4 +212,4 @@
 			step(user, user.inertia_dir)
 	else
 		return ..()
-	return
+	return