In the filter and query widgets, it would be great to use a layer's symbology to set filter icons, instead of having to manually upload as custom icons.
I use the filter widget to create "buttons" for less experienced users to easily control feature visibility of a layer with multiple categories for a single attribute. It would be nice if filter icons could easily be set to match layer symbology. Right now I use a legend to show symbology and for my filter "buttons" just use the name of the corresponding category the filter is set for.

I know I could download a png/jpeg (it would also be nice if svgs were supported) of each symbol used in the layers symbology and upload each as a custom icon, but this becomes tedious with many different categories. If the symbology is already set, it seems like there should be a way for this to be accessed.