Other issues to watch out for when food, wax, etc. is attached to the part where there is no letters, numbers, etc.
Introduction to Washing Floors on Shabbos;
What Is the Halacha When One Has a Cut on Their Foot That Bleeds When Walking?;
Replacing a Watch Band, Working with a Necklace and a Pendant or Clasp, Rubbing off Chalk Marks on the End of the Sleeve of...