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RapidWeaver Version: 7.02
System Version: 10.11.5
When copying a page in RW7, the folder name stays the same as the folder name of the page where it got copied from. If you are not aware of that, and you don’t change the name of the folder yourself, your menu will not work. The new page (copy) will point to the old page (source).
This wasn’t the behavior in RW6.
I would expect that RW7 makes the folder of a new, copied page, unique.