This 
#!/usr/bin/env perl

use 5.36.1;
use warnings;
use strict;
use utf8;
use autodie;

use warnings    qw< FATAL  utf8     >;
use open        qw< :std  :utf8     >;
use charnames   qw< :full >;
use feature     qw< unicode_strings >;

binmode(STDIN, ":utf8");
binmode(STDOUT, ":utf8");
binmode(STDERR, ":utf8");

use Text::Undiacritic qw(undiacritic);

$^I = ".bak";

my $voir = '**Voir :** proton, solution hydrogénée';
$voir =~    s/
             (?:^\*\*Voir\s:\*\*
             |
               \G(?!^)
               (?!\[))
             \K
             (\s?)
             ((\w[\/*]*)
               (?:[^\.,;\n\r]\s?)+)
             [\/*]*([\.,;])?[\/*]*
           /
  "$1\[\[glossaire:entrees:"
  .lc(undiacritic($3))
  .":"
  .lc(undiacritic($2 =~ tr[ \/*][_]dr))
  ."|"
  .$2 =~ tr[\/*][]dr
  ."\]\]"
  .(defined($4) ? $4 =~ tr[\/*][]dr : '.')
  /gemx;

print $voir, "\n";

[download]
gives me 
**Voir :** [[glossaire:entrees:p:proton|proton]], [[glossaire:entrees:
+s:solution_hydrogenee|solution hydrogénée]].

[download]
So not seeing the line break issue.

In reply to Re: Unexpected line breaks in substitution results by Danny
in thread Unexpected line breaks in substitution results by paschacroutt

Title:
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and:  <code> code here </code>
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