Https:// throws an error. How to let author know? throws

client.js:87 Uncaught (in promise) TypeError: Cannot read property 'textContent' of null
    at client.js:87
    at (<anonymous>)
    at getItemsFromFeed (client.js:86)
    at async init (client.js:273)
(anonymous) @ client.js:87
getItemsFromFeed @ client.js:86
async function (async)
init @ client.js:269
(anonymous) @ client.js:297

How to let author know?

I was able to view the website.

However, if you want to contact the author, this is their Glitch profile:

The error was not displayed at console? Am just attempting to convey that error is thrown. Not sure if that is affecting the expected result.