Scroller extension incompatible with dark themes

[D3SL]

ordinarily the table is transparent and can work with themes, provided style = 'bootstrap' is included in DT::datatable(). Per this topic at datatables the scroller extension itself sets a white background due to scroller using a diagonal striped background to show unloaded regions while the user scrolls.

Since this is upstream in DT itself I think all that should be done here is update the documentation to note the incompatibility.

It's also possible to override some of the CSS that the scroller extension adds using the below snippet just above DTOutput(), but I don't know what other issues this will cause:

          tags$style(HTML('div.dts div.dataTables_scrollBody table {background-color:transparent}')),
          tags$style(HTML('div.DTS tbody tr {background-color:transparent}')),