[latexrefman] \kern & \footnotesep

[Vincent Belaïche]

Dear Jim,

I am propagating your r633 to the French version. I fell accross this
new example in node \footnote :

\renewcommand@{\footnoterule@}@{% Kerns keep it from taking up vertical space
  \kern -3pt                         % This -3 is the negative of
  \hrule width \textwidth height 1pt % the sum of this 1
  \kern 2pt@}                         % and this 2

My understanding of the TeX \kern command is that it controls the
inter-letter *horizontal* space (see for instance
https://www.tutorialspoint.com/tex_commands/kern.htm), but here the
comments refers to vertical space. So I am a bit confused.

Your help is welcome,
   V.