When a 'Shiny' output (such as a plot, table, map, etc.) is recalculating, it remains visible but gets greyed out. Using 'shinycssloaders', you can add a loading animation ("spinner") to outputs instead. By wrapping a 'Shiny' output in 'withSpinner()', a spinner will automatically appear while the output is recalculating. See the demo online at <https://daattali.com/shiny/shinycssloaders-demo/>.
