[Request] Optional footprint polygons in volume map

[BNAndras]

Describe the feature or enhancement you're looking for Volume map viewer should optionally show the footprint/extent of layers rather the layer itself.

If this request is linked to a problem, please describe. Primarily, this would be useful in identifying bad extents like https://oldinsurancemaps.net/layers/geonode:bastrop_la_1907_p1_1. It could also be helpful for viewing the area covered by the maps without fiddling with transparency.

Describe alternatives you've considered Bad extents could also be identified by reviewing individual item thumbnails.