Apple specifically advises not to use window cleaners to clean its displays. It also advises against using household cleaners, aerosol sprays, solvents, ammonia, abrasives, or cleaners containing hydrogen peroxide here as well. Any of the above could cause irreparable damage, due to the abrasiveness of the cleaner.
Only a suitable, recommended cleaner should be used on your display, such as the ones we mention in our step-by-step guidance. Once you have this to hand, Apple reminds you to never apply it to the screen directly, as it could drip through the display and lead to more damage.