On my Perl 5.10, and latest Tk, you need to click on the 'size' header to actually get it to fill in the $mw after it opens. A hack to get around it, is to set a very high width for that column, and let it fill in from the right side.

There may be a better way. :-)

$mlb->columnInsert(2, -text=>'size',  -width=>1000  )->pack(-expand =>
+ 1);
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