Again, I think this might be better if you used “I” instead of speaking for “the user”. But let me suggest a different approach. Are you familiar with the concept of a “user story”? It’s a way to express the need for a certain functionality.
You can read more at User Stories and User Story Examples by Mike Cohn - Mountain Goat Software if this is new to you, but essentially, the form is “As this type of user, I want some thing, so that some reason.”
If I rephrase what you have said above, that comes out as:
As every user, I want a second page of notifications to be displayed when I click the expand arrow in the notification menu, so that the user interface acts as I think users expect interfaces to act based on my experience with the Facebook UI.
When put this way, I hope it is clear that this is… not a very strong user story, in all three elements.
- The user is not well-defined.
- The given goal is not really an end goal, but a specific design suggestion
- Is this expectation really generally true? Even if so, does it apply?
Or to put it all yet another way: why do you want a paginated notifications UI like Facebook? What tangible benefit would that bring you?