The notable exception being plot.py, where line-level history doesn't
really make sense.
These scripts all default to height=1, and -n/--lines can be useful for
viewing changes over time.
In theory you could achieve something similar to this with tailpipe.py,
but you would lose the header info, which is useful.
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Note, as a point of simplicity, we do _not_ show sub-char history like
we used to in tracebd.py. That was way too complicated for what it was
worth.
Christopher Haster
fc5bfdae14