Note also that the height and width of a window are passed in unsigned shorts, so that the max width of a window is 65535 pixels. There are not that many displays that are 65535 pixels wide...

You could ->pack and ->packForget in a non-scrolled Pane using the scrollbar to control which of your large array of Labels are packed. Only pack a screen widths of subwidgets at a time.

Or only create a screen widths of Label widgets, then change their contents based on the scrollbar.

Or scroll in two dimensions.

#!/usr/bin/perl

use strict;
use warnings;
use Tk;
use Tk::Pane;

my $mw = MainWindow->new();
$mw->geometry('500x500');

my $pane = $mw->Scrolled( 'Pane', -scrollbars => 'se' )->pack( -side =
+> 'left', -fill => 'both', -expand => 1 );

my $perrow = 100;
foreach my $col ( 1 .. 1000 )
  {
  my $txt = "Col $col";  # doesn't work
  $pane->Label( -text => $txt, -relief => 'groove', -height => 20,
    )->grid( -row => int +($col - 1) / $perrow,
    -column => ($col - 1) % $perrow );
  }

MainLoop;
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