Can you please let me know about the background of your project, and any modifications you have done to it, as this behavior is really strange. Do you still have templates displayed in Design->Page Templates section, and can you create new ones from there? Just to make sure we're on the same track here, please take a look at the attached screenshot and inform me if this is the option that you are missing from your project. Any additional information and a screenshot/short video describing the problem would be useful. Thanks in advance.
the Telerik team
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