#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

use List::Util qw{ shuffle };


my @browsers = ('firefox', 'chrome', 'internet explorer');
my %screen = map { $_ => "$_\'s screen" } @browsers;

my @random_array = shuffle(@browsers);
for my $b1_idx (0 .. $#random_array - 1) {
  my $b1 = $screen{ $random_array[$b1_idx] };
  for my $b2_idx ($b1_idx + 1 .. $#random_array) {
      my $b2 = $screen{ $random_array[$b2_idx] };
      say "About to compare $b1 with $b2";
  }
}
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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I wanted to say i have the same output. But it's ok indeed! It's just because sometimes, i have different sizes between browser screenshots. Compare & difference methods work with exact same size screenshots in Selenium::Screenshot package. Thanks for reply choroba !
Lost in translation

I have got one question . Why did you add 1 in line below:

for my $b2_idx ($b1_idx + 1 .. $#random_array) {
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+1

Lost in translation

To prevent an overlooked useless comparison of a screenshot to itself.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
[download]