Resolved: Perl regex: how to get multi-byte optional char (?) matching

Question:

With single-byte chars optional matching works:
With unicode (wide-byte) chars optional matching does not work
How to make it work? I’ve already added /u and I’ve tried use feature 'unicode_strings' to no avail. I assume perl sees д as multiple bytes and only applies ? to the last one.

Answer:

You have to tell Perl that the source is in UTF-8:
See utf8 for details.

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