It often depends on what widget you are using and what is focused at the time of the right-click. Some widgets will have built-in bindings for different mouse clicks, like the Tk::Text widget. Play with this, and notice the difference when you uncomment the line Tk::break.

#!/usr/bin/perl
use warnings;
use Tk;
use strict;

my $main = new MainWindow;
$main->geometry('200x200');

$main->Button(-text=>"click",-command=>sub{
          print "Button left click\n";
         })->pack;
   
$main->bind('Tk::Button', '<ButtonRelease-3>', \&some_sub);

$main->bind('<ButtonRelease-3>', \&some_other_sub);
   
MainLoop;
   
sub some_sub{
    print 'Button ',scalar gmtime,"\n";
    
    #Tk::break;  #stops the main window binding from activating
}

sub some_other_sub{
    print 'main window ',scalar gmtime,"\n";
}
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