I want to know that is it possible to add new icon before the Notification icon and call some JavaScript stuffs in SharePoint Online using JavaScript?
If yes then how we can achieve it using JavaScript or JQuery or Powershell?
Try below code in Script Editor:
<script type="text/javascript" src="http://code.jquery.com/jquery-1.2.6.min.js"></script>
<script type="text/javascript">
$(document).ready(function() {
//Define new links
var newLinks = "<li class='ms-core-suiteLink'> \
<a class='ms-core-suiteLink-a' href='http://extranet.crescent.com'>Extranet</a> \
</li> \
<li class='ms-core-suiteLink'> \
<a class='ms-core-suiteLink-a' href='http://support.crescent.com'>Customer Support</a> \
</li> ";
$('.ms-core-deltaSuiteLinks').prepend(newLinks);
alert('works');
});
</script>
Hope it works for you.
Reference Link: http://www.sharepointdiary.com/2015/09/how-to-add-link-to-sharepoint-2013-suite-bar.html