IMHO, stage snaps can be thought of sorta like content snaps at build time. With content snaps we have the notion of naming the “content” field in a way that expresses where it came from and very course versioning (eg, “gnome-3-26-1604”). Stage snaps on their own don’t have this concept inherently so a track request does make some sense.
That said, I wonder if it makes sense for the ffmpeg snap to provide a content interface with a similar naming convention that when you stage it you get those libraries. Admittedly, this is stretching the concept of the content interface as well.
@pedronis - I don’t typically vote on track requests, but considering @noise comments in Track request(classic) for the tree snap, to be safe, could you weigh in on the concept of using tracks for stage snaps in this manner? Perhaps @roadmr could update the documentation if needed. Thanks!