Here is something you might work on; you can turn off the overrideredirect flag. Possibly you could work out a system to remove the flag when you need to place something on top, then restore the flag when done. 
#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $mw = tkinit;
$mw->geometry("200x300+200+200");

$mw->overrideredirect(1);   # set the override-redirect flag
$mw->packPropagate(0);      # prevent the window being resized
                           # for this demo
$mw->Button(
   -text       => 'Quit',
   -command    => sub { Tk::exit(0) },
)->pack(
   -side       => 'bottom',
);

# after a delay:
# withdraw
# clear the override-redirect flag
# re-map the window
$mw->after(
   4000,
   sub {
       $mw->withdraw;
       $mw->overrideredirect(0);
       $mw->deiconify;
       $mw->raise;
   }
);
# NB:
# "Mastering Perl/Tk" mentions that clearing
# the override-redirect flag will not cause
# the window manager to supply decorations.
# This is true, but at least on KDE, clearing
# the flag, then unmapping and mapping the
# window puts decorations in place.
#
# Your mileage may vary.

MainLoop;

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In reply to Re: Prevent overidedirect from being always on top by Anonymous Monk
in thread Prevent overidedirect from being always on top by Anonymous Monk

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