Modify Title of UI dashboard page <head>

I'm looking for ways to modify the title of my UI dashboard in section in order to become visible from search engines.

I still get the html source code below and would like to fille the <Title></Title> section and remove the <h2>Welcome to the Node-RED Dashboard</h2>

I tried something with the template node with no success. See screenshot below :

Thanks for you help.

--> <html lang="en" manifest="dashboard.appcache"> 
<head> <meta charset="utf-8"> <meta name="viewport" content="width=device-width,initial-scale=1"> 
<meta name="apple-mobile-web-app-capable" content="yes"> <meta name="apple-mobile-web-app-status-bar-style" content="black-translucent"> 
<meta name="apple-mobile-web-app-title" content="Node-RED"> <meta name="mobile-web-app-capable" content="yes"> 
<link rel="manifest" href="manifest.json"> <link rel="icon" sizes="192x192" href="icon192x192.png"> 
<link rel="shortcut icon" type="image/png" href="icon64x64.png"> <link rel="apple-touch-icon" href="icon120x120.png"> 
<link rel="stylesheet" href="css/app.min.css"> <title></title> <link rel="stylesheet/less" href="css/app.min.less"> 
<body ng-app="ui" ng-controller="MainController as main" ng-cloak layout="column" style="background: {{main.backgroundColor}}" class="nr-dashboard-theme" ng-swipe-right="onSwipeRight();" ng-swipe-left="onSwipeLeft();"> 
<md-content ng-if="main.loaded" ng-include="'partials/main.html'" layout="column" flex></md-content> <div ng-if="main.nothing" class="node-red-ui--notabs"> 
<table><tr><td><center><img src="icon120x120.png"></center></td></tr> <tr><td><center>
<h2>Welcome to the Node-RED Dashboard</h2></center></td></tr> <tr><td><center>Please add some UI nodes to your flow and redeploy.</center></td></tr></table> </div>
<!-- <i class="fa fa-spinner fa-spin fa-4x fa-fw"></i> --> 
<script src=""></script> 
<script src="js/app.min.js"></script> <script src="i18n.js"></script> 
</body> </html> <!--</Deject>--> 

The section of my UI doesn't modify with ui_template node. I would like to modify in order to become visible from search engines.
Thanks for your help.

It is set in the Site section

Thanks @dceejay ! But I already fulfilled this section.
There must be something wrong somewhere.....
See - Screenshot