//wait for mw.util
mw.loader.using( 'mediawiki.util', function () {
	$(function() {
		console.log( '$content is ' + (mw.util.$content === null ? '' : 'not ') + 'null in jQuery.ready');
	});
	//mw.util.callback is provided by the patch
	if (!mw.util.callback) {
		return;
	}
	mw.util.callback.add(function() {
		console.log( '$content is ' + (mw.util.$content === null ? '' : 'not ') + 'null in mw.util.callback');
	});
});