After different tests, I can confirm that the Kendo UI CSS has to be loaded inside the boot-client(server).tsx file.
I can assume that this is a species of the template project that is created.
Also, please have in mind that the components are requiring React 16+, but the template is usually created with 15+.
If the issue still occurs, please send an example reproducing the issue and will gladly assist further.
Regards,
Stefan
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