This scenario is a bit hard to explain but it happens quite a bit. Say you have a Browser control, then you add a bunch of elements to it.
At some point you decide to add a Rectangle to use as a background to part of the page. If you just select it and send it back, it will go behind the browser.
Instead, SHIFT+CLICK to select the browser as well, and THEN send both back together! Their relative stacking order will be maintained and voila'!
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