Other issues to watch out for when food, wax, etc. is attached to the part where there is no letters, numbers, etc.
How to Deal With Putting Items Into the Refrigerator, for Example Sodas, That One Will Need for מוצאי שבת (Motzei Shabbos);
Understanding the Concept of Something That Was Attached to the Ground or a Tree Going into Shabbos and Then Became Detached on Shabbos (Muktzeh);