Convert a domain to and from Punycode, and see whether it could be imitating another.
Either the readable form or the xn-- encoded one.
xn--mnchen-3ya.de
This domain contains characters outside ASCII, so it is registered as xn--mnchen-3ya.de and only rendered in its readable form by software that chooses to. That gap is what homograph attacks use: Cyrillic а, е and о are visually identical to their Latin counterparts in most fonts, so a domain can be indistinguishable from a brand it is imitating while being an entirely different registration. Browsers defend by showing the Punycode form when a label mixes scripts, which is why a suspicious domain sometimes appears as xn-- in the address bar.
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