Great thanks!
When searching in the web, I only found some (obviously outdated) information that there would not exist reliable ways to check the UTF-8 bit.
So is_utf8() was exactly what I needed to circle in the problems'cause.
Turned out that HTTP::Tiny does not support Unicode, just raw text.
Thus the issue was resolved by UTF-8-encoding its byte string data through decode().

In reply to Re^2: How to set the UTF8 flag? by dissident
in thread How to set the UTF8 flag? by dissident

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