sure the href link is visible. if not used, the link text is not shown.
	function showAbout() {
		showMessage(
			'About...', 
			'<style>a:link{ color: blue; background-color: transparent;</style>' + 
			'<p style="font-weight: bold;">Weather Forecast 9-DAYS</p>' + 
			'<p>Source: Weather forecast delivered by the <a href="http://met.no" target="_blank">Norwegian Meteorological Institute</a>.</p>' +
			'<p>Credits: Solution based on <a href="https://jsfiddle.net/gh/get/library/pure/highcharts/highch