Yes, truncating a user facing string requires more consideration regardless of programming language. For example do you truncate at the grapheme, word, sentence, new line, paragraph, or something else? How do you indicate truncation to the user, with an ellipsis perhaps? If you use an ellipsis is it appended to the original string or drawn by the GUI toolkit?

Note that the Unicode grapheme cluster, word, sentence, and line break algorithms are locale specific. Now consider how often programmers casually truncate strings, even in high-level languages, without accounting for the locale.