Nowhere in this paragraph does he say exactly where he typed the characters.
He says he created an empty folder and then that he typed 'ALT+015…'
Where?
-Did He name the folder ALT+015…?
-Did he make a text file with 'ALT+015…' written in it and put it inside the folder?
-Did he type 'ALT+015…' somewhere in the tree preferences?
'I did this by creating an empty folder (i.e. a folder with nothing in it) and using em-dashes to make it appear like a line. You can type an em-dash in Windows with ALT+015…'