Hi Mark,
Thank you for contacting us.
You are correct, this is the modern behavior for underlining the hot keys used in Windows Vista. Currently
RadMenu supports only the classic behavior, when the underlining is always visible.
We have plans to support the new behavior, however I can't give you exact time line when it will be implemented. We will be happy to raise the priority of this feature if we see more interest in it.
Do not hesitate to contact me if you have other questions.
Thank you
All the best,
Jack
the Telerik team
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