grep fails to find non-Latin-1 Unicode characters

[fmeum]

Description / Steps to reproduce the issue

In the MSYS2 shell, run:

echo "äöüÄÖÜß🌱" | grep -F "äöüÄÖÜß🌱"

Expected behavior

Output:

äöüÄÖÜß🌱

Actual behavior

Empty output, no match.

Verification

• I have verified that my MSYS2 is up-to-date before submitting the report (see https://www.msys2.org/docs/updating/)

Windows Version

MSYS_NT-10.0-22631

Are you willing to submit a PR?

Yes, but I would need some help as a first-time contributor to the project