I think what you are seeing, and thinking is a menu button, is actually some text that is presented when you mouse over a button. Since that text ‘hovers’ over another button it might seem you are clicking on a button but getting a different menu item’s link.
There’s probably some documentation at the theme’s support area to help you understand that ‘feature’ and adjust it or else disable it.
]]>If you click the link and just hold down instead of releasing, you can see the size of the “selection field.”
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