Broken Try GNU Libidn page

[Sidney Markowitz]

No matter what I try in the page https://josefsson.org/idn.php (Try GNU 
Libidn), including all of the Examples links, the result is the same:

Output
$ CHARSET='' idn --idna-to-ascii '' 2>&1
idn: tld_check_4z: Missing input
$

I'm reporting it as per the instructions on the page
"If you encounter a problem with this page, write a (detailed!) report 
to bug-lib...@gnu.org."

I tried this on a Macbook using both Chrome and Firefox with my ad 
blocker disabled on the page.