How to add a separator between menu items in a wp_nav_menu() the easy way
WordPress wp_nav_menu() function has lots of useful arguments for customizing your menu, but it's missing an essential one: a menu item separator. For example, if you want to add a | (vertical slash) or a · (middot), or any other separator of your choice, the ideal solution would be to add it as a function argument like
'item_sep' => '·'