Just a week or so ago, I had to go through a process of renaming a bunch of pdfs because they included diacritics (e.g. á, ü, ç) in the file name and dropbox wouldn't upload them. I accidentally added a file with a diacratic today and it worked. Is this issue finally fixed? I can't find any update news saying this was changed, but it appears to work for me know. Just wanted to double check before I start allowing for them in my filenames again.