… that you could stick labels on glass with milk?
Pour milk in a small bowl then dip the back of the label in the milk (or use a paintbrush). It has to be quick so the ink on the top of the label doesn’t leak. But make sure the whole back is covered with milk.
Place the label on the jar and hold it for a few seconds. You can use paper towel to hold the label and absorb the excess of milk.
The label is now fixed!
(But you can easily remove it if you want to re-use the jar.)