Tbf, the article is from 2018. It possibly has changed in the meantime.

Recently it has become a problem that optical twins of legit URLs exist, where some letters have been replaced by alike letters (homoglyphs) from different alphabets, see e.g. the list in this link.

Edit: Edge and Vivaldi seem to replace those letters by Punycode automalically, where in Firefox network.IDN_show_punycode needs to be enabled in the about:config.
bleepingcomputer.com

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