I greatly apologize for the delay in answer.
The textbox part of the autocomplete should not look like that at all. That's either a bug or there is additional styling on the page for inputs, that overrides ours.
By any chance, do you have RadFormDecorator or another styling framework on the page?
If not, would it be possible for you to isolate the problem to a single page that always produces the issue and attach it to this ticket?
For this report, and the great delay in answer, I am awarding you some Telerik points which you can see updated in your account profile.
In addition, we would really appreciate any feedback on the autocompletebox experience you may have. As you know, that's our youngest control so we may have missed something about the process and experience.
the Telerik team
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