showing TimeSignatures on each line?

[Evan Laforge]

In music where the time signature changes a lot, it's nice to show the
time signature on each line even when it hasn't changed.  Is there a
way to get that to happen?

I experimented with the (undocumented?)
TimeSignature.break-visibility, but even with (#t #t #t) it doesn't
seem to have any effect.

I saw a question from 2015 asking almost the same thing, but with no
answer, so maybe it would need c++ level modification?