Deep

Maybe in billions of years or whatever when they die and their matter takes forms, assuming the universe heat death isn't a thing yet

The stars are too far along in their lifecycle. Nebulae have the possibility however.

Too far along? Please explain, because don't the stars send out their elements that they made when they die of age? Creating heavier and heavier elements until they inevitably die?

Large clouds of hydrogen can produce supermassive stars which, when they run out of hydrogen move to helium and then on down the periodic table until they hit iron. Iron is too stable to fuse so all the heat makes them explode into nebulae. After a while the particles of the nebulae begin to come together and form a whole bunch of stars like our sun as an example and planets are a sort of byproduct. These stars aren’t massive enough to follow the same pattern of creating a nebula and then new stars and planets.