There is a change in the 4.8 beta that is being backported to 4.7 so that all users can receive the performance benefits. Library folders coming out of the api will have their Id populated with the numeric database id rather than a guid.  Fortunately, most plugins or api users won't require any changes, but here are some best practices to follow. These changes will work with server versions 4.6+ and are both backwards and forwards compatible, so they don't require you to target a specific s