We had a delivery from xkcd store delayed by one month because of few characters with diacritics, which the xkcd store software couldn't handle, and the package

We had a delivery from xkcd store delayed by one month because of few characters with diacritics, which the xkcd store software couldn't handle, and the package was sent back as undeliverable because of the unreadable address. And that was latin script, with just few diacritic marks (mostly just ASCII), I can't imagine what would happen with some non-alphabetic script… And that is far too common. On the other hand, modern desktop software (either OSS and MS) is, thankfully, quite OK, nowadays.