Hi Luis, 
>> doing kind of fancy borders like that is somewhat laborious in HTML. 
> 
> I would've thought differently. but ok.
 
Some kinds of things can be quite annoying to do in HTML - the particular tricky thing about the flyout border is that it's not just a static border, it has a connector piece that's variable width, that expands to match the launching element's size.
 
Here are a couple of examples where you can see the difference in the width of the connector piece of the border:
     
Then on top of that variable width part, the connector can also go on any side of the window, like above you see one is on the bottom-left and the other is on the top-right.
 
Here's one with the connector on the side:
  
That flyout border thing is quite a bit more complex than you might think it is at first glance.
 
    - Michael  
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