Roman Žilka authored Jul 31, 2023 and Craig Small committed Oct 06, 2023

* Because 's' is synchronous, it's become necessary to indicate when is cmd
  running. Without it the user may not be sure whether a 's' will save the
  output currently on-screen or the next iteration output. The blank lowheader
  is relatively unobtrusive, but might suggest that the timestamp in header is
  the time of cmd completion. Also, it puts potentially time-consuming I/O
  between cmd iterations. Still, the best option I could think of. Header
  semantics is given in manpage.