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When setting the focus
to the RadAutoCompleteBox from a RadRichTextBox control indeed the RichTextBox's caret does not disappear. Other that that visual effect the observed behavior was correctly
triggered and the input string was taken from the RichTextBox and passed to AutoCompleteBox correctly.
I recorded a short video for you showing the observed scenario on our side. Could you verify that this is the visual caret (focus) issue you are experiencing? You can also find the sample test project used in the video attached to my response.
If we have missed something please respond to us in a separate support thread where we can continue the discussion in greater details.
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