When editing level geometry, be it via Terrian sculpting or ProBuilder, having Progressive Lighmapper on Autogenerate by default yields a really bad user experience because of bad perfoemance and the annoying blue texture that appears all the time.
While I understand that Progressive Lightmapper is actually a great feature, I don’t think that having it on by default, from the very start of the project is something an advanced Unity user would do, and I’m even more concerned that a new user won’t understand what it is, what is happening and will just flag this behaviour as a bug!
Some other solution is needed for the default 3D template settings.