EN should format document you are working on, not the last one opened

A very frustrating change has taken place in one of the latest editions: if you open a document after the one you are working on, EndNote automatically formats that one.

You have to manually select the document you are working on from the window, each and every time.

This is time consuming and unnecessary.  It is more flexible to have a system where you can simply bring a document to the front when you want to deal with that, rather than the software choosing for you.

Could you tell us your exact version of Word, EndNote and operating system please?