bug#27647: 26.0.50; Line numbers implemented natively disappear momentarily when frame out of focus

[Eli Zaretskii]

> From: Noam Postavsky <npostavs@users.sourceforge.net>
> Date: Wed, 19 Jul 2017 13:52:28 -0400
> Cc: Kaushal Modi <kaushal.modi@gmail.com>, 27647@debbugs.gnu.org
> 
> Perhaps 'watch Vdisplay_line_numbers' in gdb would help?

I thought about that, but I'm afraid it could cause an infinite series
of unrelated hits, each time Kaushal switches between buffers.  It may
make editing impractical.

But if I'm mistaken, why not?