To quickly identify logical groups on page, on the View menu, tick Logical Group Order. This shows the special logical group labels whereas:
•The G:1 label marks the first frame in the given flow (e.g. flow of body frames), telling you also that the frame was not created by a library object, but manually.
•The LG:1 label marks the first frame in the given flow (e.g. flow of body frames), telling you also that the frame was created by a library object.
•The 1 label marks the first frame in the given flow (e.g. flow of body frames), telling you also that the frame is not part of a logical group.
The frames marked with 1,2,3,4 without any additional letter are not part of logical groups. The frames marked with G:1, G:2 etc are part of logical group, generated not from a library object.
The frames marked with LG:1, LG:2 etc are part of logical group, generated from a library object.