Simplifies DOM Level 0 API implementation via Level 3 listeners.
withLevel0('anyname');
const div = document.createElement('div');
// add listener
div.onanyname = event => {
console.log(event.type);
};
// test it: will log "anyname"
div.dispatchEvent(new Event('anyname'));
// clean up
div.onanyname = null;
// test it's clean: nothing happens
div.dispatchEvent(new Event('anyname'));
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