I cannot localize the messages of the Angular and React report viewers using the suggested approaches:

• Angular Report Viewer Localization - Telerik Reporting
• Localizing the React Report Viewer - Telerik Reporting

The only alternative is to use the approach from the Localization of the HTML5 ReportViewer Explained - Telerik Reporting article, which I can do only by loading the string resources script in index.html of the SPA.