Ok, I refreshed and tried again.

   Climb in mailbox

   You approach the small mailbox and try to climb inside, determined to fit yourself within its confines.

   You attempt to climb into the small mailbox, but end up bumping your head against its narrow opening. It's simply too small for anyone to fit inside; only letters and parcels can enter here.

   Become a letter

   You focus deeply, willing your body to transform. You feel yourself grow flat and light, edges crisp, your form now that of a letter—thin enough to slip through any mail slot and fit inside the mailbox with ease.

   Enter mailbox

   Now shaped like a letter, you slip smoothly into the mailbox. The inside is dark, cool, and the metal walls surround you on all sides. You rest quietly, perfectly at home in this new form.