TypeError: Cannot set properties of null (setting 'now')

1 개요[ | ]

Exception in module-execute in module ext.visualEditor.ve
TypeError: Cannot set properties of null (setting 'now')

/app/w/extensions/VisualEditor/lib/ve/src# grep -rn 've.now()'
ve.Filibuster.js:162:   var time = ve.now() - this.startTime;
ve.Filibuster.js:316:   this.startTime = ve.now();
ve.track.js:25:         queue.push( { topic: topic, timeStamp: ve.now(), data: data } );
ve.js:29:       return ve.now();

ve.js

/*!
 * VisualEditor namespace.
 *
 * @copyright 2011-2020 VisualEditor Team and others; see http://ve.mit-license.org
 */

/**
 * Namespace for all VisualEditor classes, static methods and static properties.
 *
 * @class ve
 * @singleton
 */
window.ve = {};

/**
 * Get the current time, measured in milliseconds since January 1, 1970 (UTC).
 *
 * @return {number} Current time, monotonic in modern browsers (via Performance Timeline API)
 */
ve.now = function () {
	// Based on `mw.now` in MediaWiki core.
	// Optimisation: Cache and re-use the chosen implementation.
	// Optimisation: Avoid startup overhead by re-defining on first call instead of IIFE.
	var perf = window.performance;
	var navStart = perf && perf.timing && perf.timing.navigationStart;
	ve.now = navStart && perf.now ?
		function () { return navStart + perf.now(); } : Date.now;

	return ve.now();
};

2 참고[ | ]