Press <Tab> in that Tk window. See? You want 
    $canvas->configure(-highlightthickness =>0);

[download]

:-)

update: I see you found out while I was writing the answer... highlightthickness is the width of the highlight border (default 1 pixel). If you set it to 0, the element will not highlight while cycling through the elements with <Tab>, since there is nothing to colour. If you want to leave the border there, use 

    $canvas->configure(-highlightbackground => $background);

[download]

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re: Undesired space between Tk Canvases by shmem
in thread Undesired space between Tk Canvases by liverpole

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