Thank you for your interest in RadRichTextBox!
Due to the current implementation (the control contains a number of additional UI elements in its visual tree), its expected that RadRichTextBox would raise additional GotFocus/LostFocus events in some cases. As far as we tested, however, the LostFocus event of the RadRichTextBox is not fired repeatedly when typing each character in the control. Could you give us more information about your scenario and what are you trying to achieve, as we may be able to suggest you better approach?
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