Since the commit c129087eb0 for MBS-3208 in 2012, non-printable characters have started to be removed or replaced with whitespaces, de facto forbidding the use of whitespace variants in newly edited data.

However, some of these characters have already been entered either before 2012 or in not trimmed fields:

• U+3000 IDEOGRAPHIC SPACE for Japanese, see MBS-5555,
• U+00A0 NO-BREAK SPACE for French, see MBS-9576.

And there are even more variants, see whitespace characters in Unicode but line-breaks. Most of these characters are used in real releases and, as such, should probably be allowed to be entered in the database.