Hello Denis Vuyka,
As of Q2 SP2, unfortunately, there is no available API to achieve this functionality. However, luckily, in the Q3 beta, which is coming very soon, there will be HyperlinkClicked events on the RadDocument and RadRichTextBox which will allow you to handle the event yourself and eventually, suppress the default behavior.
Feel free to get back to us if you have any further questions.
the Telerik team
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