FM 2017 - Merging content from a .fm file to another

Scenario: We have a team member updating a FM document for product A Release 1. We have another team member updating the a copy of the same document for product B Release 2. The FM document is a common configurations document to both product A and B.

Product A releases before product B. The first version of the FM document will go for product A Release 1. To ready the document for product B Release 2, I want to merge content from my copy into this.

Question: A simple copy and paste would address this. But is there another smarter way to merge content from 1 .fm file into another?