You'll prob have to run shockcord from the ridgeline or from side tieouts. I'm afriad without a firm anchor the result would be less than desirable. I've seen it done with grossgrain loops, shockcord, & mitten hooks. If you anchor well, and make sure that button is very well secured, maybe even backed with a small scrap of 1.9oz nylon. You wouldn't want the button to tear through your down quilt's shell and expose the goosey goodness.
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