but removed it for clarity

I'm not sure how the extra two lines at the top and two additional mys detract from clarity, but each to their own :)

[16:18:28.03] C:\test>type junk.pl8
#! perl -slw
use strict;
use Tk;
use threads;

my $mw = new MainWindow;
$mw->minsize(qw(300 50));


$mw->title("Main thread window");
my $button = $mw -> Button(-text => "Fire Thread",
        -command => \&fire_thread)
    -> pack();

print "from Main thread ", $mw, ":::",$mw->id,"\n\n";

sub fire_thread {
 my $t = threads->create(\&worker_thread);
 $t->detach();
}

sub worker_thread {
$mw->title("Worker thread window");
print "from Worker thread ", $mw, ":::",$mw->id,"\n\n";
}

MainLoop;
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