s{Password=\Q$password\E}{Password=$newpass} if $answer =~ /y/i;

##</code><code>##

my $sentence = 'The quick brown fox jumped over the lazy dog';
my $substring = 'quick.*?fox';
$sentence =~ s{\Q$substring\E}{big bad wolf};


##</code><code>##

#!/usr/bin/perl

use strict;
use warnings; 
use Tie::File;

my $filename = '/home/stain/Downloads/REMOTEopen.xml';

tie my @array, 'Tie::File', $filename || die "Cannot tie file $filename to array: $!";

foreach my $line (@array)
{
    my $newline = $line;    # Make a copy


        while ($line =~ / <Node \s+ Name="(.*?)" .*? Password="(.*?)" .*? > /mgx)
        {
        my $name = $1;
        my $password = $2;
        print "Enter the plain text password for $name, ",
              "password is currently $password\n";

        chomp(my $newpass = <>);
        print "You will now swap $password for $newpass\n";
        print "Continue? (y/n)\n";
        chomp(my $answer = <>);

        # Change the copy

        $newline =~ s{$password}{$newpass} if $answer =~ /y/i;
    }
        $line = $newline; # Update this line in the file

}

untie @array
    or die "Cannot untie file '$filename': $!";