I tend to use the form geometery manager as it provides a good deal more control when resizing. Try the following code:

use strict;
use warnings;
use Tk;

my $main = MainWindow->new (-title => "Demo");
my $txt = $main -> Scrolled('Text',-width=>57,-height=>5,-scrollbars =
+>'osoe');
$txt->form (-left=>'%0',-top=>'%0',-bottom=>'%100',-right=>'%100');
$txt->Insert ("text\n\n\nMore\n\n\nand more");
MainLoop ();
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