This sample shows a issue of Apple PDFKit when making changes to PDF files.
This example has a Highlight text feature, select a text, tap "Highlight" on Touch Bar, changes will automatically save.
PDFDocument.write(toFile:) (document) breaks vertical writting PDF documents.
Find a vertical writting PDF document that text can select vertically.
Download the example doucment.
Check if document text can be select vertically.
Open this document in PDFReader-Mac.
Select a text, tap "Hightlight" on Touch Bar.
Close and open file again.
You can see vertical text selection is broken.
