Requirements for adding and displaying the HTML5 Report Viewer.
The viewer requires a running instance of Telerik Reporting REST Services in order to display reports.
Required HTML5 compliant browser. For more information see: Browser Support
Kendo UI Professional license is not required if you are only going to use the demanded pro widgets for the needs of HTML5 Report Viewer. Telerik Reporting provides a JS file containing a subset of the used by default Kendo UI widgets - telerikReportViewer.kendo-x.x.x.x.min.js. For more information refer to Telerik Reporting License Agreement (point 4.2).
The required CSS and Js files must be loaded before creating the HTML5 Viewer on the page.
jQuery must be loaded only once by the page with the HTML5 Viewer;
If you use a CDN to load the required CSS and JS files, verify the links are run over HTTP or HTTPS depending on the hosting of the application.
The HTML5 Viewer is designed to request its HTML template from the resources of the Reporting REST Service. If you will not add changes in the default template, you do not have to specify the HTML template. The HTML template includes links to the HTML5 Viewer's CSS template file and icon fonts, also available through the resources of the HTML5 Viewer.
For more details, check Styling and Appearance
The viewer depends on the browser's native implementation and support for promises. When the browser does not support promises the viewer will automatically load a promise polyfill from Polyfill.io. If you would like to use your own polyfill, you can load it in your application. The viewer will check whether a polyfill is already loaded and will not try to load another one.