I'm trying to get a list of all cities and timezones using moment-timezone in React.

import moment from 'moment-timezone';
const timezones = moment.tz.names()
console.log(timezones)

What I've got is an array with 594 elements and most of the cities are supported. But still, there are some timezones that don't exist in the array. For example Europe/Milan or America/Ohio or America/Washington D.C and America/Montreal. How can I get a list of timezones? Are all of the timezones supported by Javascript?