Clear nail polish has long been used to stop a “run” in stockings–it goes on easily, dries quickly and acts as a glue to keep threads close together.
You can also use this wonderful substance to keep buttons from popping off your shirts and sweaters. This works for two-hole and four-hole buttons. Start with a clean, dry, and unbuttoned garment. Brush the polish across the center of the buttons, covering the threads. Allow 10-15 minutes to dry, and then add an second coat. Once dry, the polish fortifies the threads, keeping them from breaking, and keeping your buttons in place.