05 vs 04 Headliner

Had an opportunity to drive a friend's 05 Silver Prius the other day. The only difference in her car vs mine is that the headliner had two plastic support plugs, or screws, located just behind the front seats. (I just looked up and had a "what the heck is this" moment) I am assuming this is the quick fix Toyota has developed to solve the sagging headliner problem, should that occur.
Has any 04 owner had these plugs or support screws installed in their car? My headliner appears to be just fine but thought if it was a good cheap installation I may avoid future problems.
Thanks!