We are not aware of any big performance hits of the Menu, especially if its structure is simple. Since the Menu is only processing elements within itself, the only possible issue I can think of is a non-properly closed or incorrectly nested tags, which to cause it to start evaluating the rest of the page elements, that are not intended to be in the Menu. Can you use the ticket you've sent to send a sample page with the issue isolated, so I can check what is happening? Thank you in advance.
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