in reply to utf8::is_utf8 valid introspection?
If you need to work around a bug, just use
utf8::upgrade($var);
or
utf8::downgrade($var);
to get the the string in the expected storage format (regardless of the current storage format).
The only use I can think of for utf8::is_utf8 is for debugging, but I use Devel::Peek's Dump when I want to peek at a scalar's internals.
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