All of the above: I interpret "Full Stack" to mean mostly web front-end. It generally doesn't mean mobile or desktop. It does also include back-end development

All of the above: I interpret "Full Stack" to mean mostly web front-end. It generally doesn't mean mobile or desktop. It does also include back-end development but the trend is to use more off-the-shelf solutions and services so that there's less of it than there used to be. The reduction in back-end coding is taken up with the expectation that the "most commonly used functionality" is now in scope. + what other comments say where they want multiple specialists but are hiring one position for flexibility or cost.