FR: Expand mulitple items by default

[knobunc]

I received a bunch of separate single-page PDFs that are part of one update and I have grouped them into one item.

But it's not obvious when I view the item later that there are multiple docs in the single item.

It would be a nice usability enhancement to auto-expand the multi-item disclosure if there are multiple docs in an item. (Perhaps as a user-definable option)