Install idn by entering the following commands in the terminal:
sudo apt update sudo apt install idn
Description:
Command line and Emacs interface to GNU Libidn
GNU Libidn is a fully documented implementation of the Stringprep, Punycode and IDNA specifications. Libidn's purpose is to encode and decode internationalized domain names. The Nameprep, XMPP, SASLprep, and iSCSI profiles are supported. . This package contains the idn command-line tool and its Emacs lisp interface.
Homepage: https://www.gnu.org/software/libidn/
Version: 1.33-2.1ubuntu1
Section: universe/misc