She had the IPA symbol for the sh sound. The square was the Mac's miserable attempt at displaying it. I saw it properly on my PC at work. I copied and pasted into a .txt file and did a hex dump of the file. It showed up as a three byte Unicode something or other. Anyone interested I'll look it up when I get back to work. It was 00 83 20 or something like that.

My "superior Mac" comment was irony