I'm not familiar with such a problem and I'll need more information about your setup to be able to help you.
RadEditor is a standard ASP.NET WebForms component and it does not offer a functionality to temporary display and hide it on the page. Is it possible to provide a live URL to the problematic page or a simple working project which demonstrates the problem? The problem could be related to some custom code or CSS that hides the component. You can try to isolate the control by removing parts of the page contents until you are able to find the culprit for the issue.
Are you able to reproduce the issue with the latest version and in the live demos of the control
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