Controls area exceeding screen height?

[rsimon]

We may need a strategy for when the controls area exceeds the screen height. This is less of an issue om desktop. But on mobile things get dense. E.g. when there's a selection that includes a depiction, and an open filter panel, the result list height < 1 item (which makes it unusable, even if ther's currently no resul list header.)

In the future, we'll have an additional collapsible area in the filter pane, to show facet distribution bars. In this case, the result list will simply vanish.

What to do? Either force elements into an alternative "collapsed" representation? Or make the whole controls sidebar scrollable?