Please have a look at this site: https://kso.etjanster.lantmateriet.se/?lang=en# and click the binoculars in the left sidebar and search for e.g. "ESKILSTUNA KARLKULLA 1:2" you will see a multipolygon, one property with two sites, getting highlighted. I thought this was only possible to do with a WFS, but is it also possible to do with a WMS (it looks like they use WMS...?) - and if so, how is it done?
Or do you have any ideas how they have done it? Combining both WFS and WMS on top of each other?
I'm using GeoServer to cascade this remote WMS boundary layer and then display it on a Leaflet map.