I don't have an answer for you but I can confirm what you're seeing. I also ran some additional tests. I'm using: macOS Sierra 10.12.5; Perl 5.28.0; Tk 804.034; XQuartz 2.7.11; and, xorg-server 1.18.4.

Firstly, for all tests, I wrapped the code you posted in: 

#!/usr/bin/env perl

use strict;
use warnings;

use Tk;

my $mw = MainWindow::->new();

...

MainLoop;

[download]

[It's best to show code that can be run directly. It makes it easier for us to test. It also means that a potential problem, in the code you haven't shown, can be detected. SSCCE has more about this.]

With your code, I see a ".apple" menu button which has an empty dropdown list. The system (apple-icon) menu is unchanged.

I added this line (after "my $applemenu = ..."): 

$applemenu->command(-label => 'Hello', -command => sub { print "Hello\
+n" });

[download]

The ".apple" dropdown list now has this item which works as expected. Again, the system (apple-icon) menu is unchanged.

I also tried without the toplevel: 

my $menubar = $mw->Menu(-type => 'menubar');
...
$mw->configure(-menu => $menubar);

[download]

This also works for the ".apple" menu; but the system (apple-icon) menu is still unchanged.

I'll front-page your post to give it a wider audience as I'd anticipate reduced attendance over the next few days. I'm also personally interested in an answer to this. [Update: haukex front-paged it while I was composing my reply.]

Finally, just as a side note, Perl's Tkx and Tk are both based on tcl/tk. Tkx is just a thin wrapper around it. Tk uses code based on it; for example, see the first line of the Tk::Menu source: 

# Converted from menu.tcl --

[download]

Although both have superficial similarities in various places, they are quite different. As a quick example: 

$mw->Button(...)->pack;       # Tk
$mw->new_button(...)->g_pack; # Tkx

[download]

— Ken

In reply to Re: Tk menu Apple macOS by kcott
in thread Tk menu Apple macOS by Anonymous Monk

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