Listen for all events in JavaScript

A more modern rewrite of @roman-bekkiev’s answer:

Object.keys(window).forEach(key => {
    if (/^on/.test(key)) {
        window.addEventListener(key.slice(2), event => {
            console.log(event);
        });
    }
});

Note that you can further customize what you want to catch, for example:

/^on(key|mouse)/.test(key)