In map viewer it is possible to switch between base maps with different projections (in this case default ESRI base maps and ordnance survey base maps (ESPG:27700) with all the layers I am using. In the web builder app (and also the experience builder app) it is only possible to select from base maps that are of the same projection of the base map that is saved in the map. Is it possible to allow more than base map projection in an app?
