KAddressBook: Show address on map in browser

How can I set which website is used to display an address in the browser when I click on it in KAddressBook (Kontact 6.5.1)?

I think Systemsettings → Default Applications → Map

Works. Thanks.

But how can I change the setting? Apart from OpenStreetMap, the only option is to select an installed application.

How can I specify which website to use?