Clicking the icon moves that filter to the top section of the drop-down list to indicate that it is selected, and makes that filter available to the chart when viewing the dashboard. Here, quick filters have been enabled for FR, CA, IT, JP, US, and IN. IT is currently selected, and the chart information reflects that filter application. This makes it easy to apply high-priority filters to individual charts and see the results quickly, and do side-by-side comparisons of identical charts with different filters applied. To remove the chart-specific filter, click All.