This is what I did:
Duplicate Site in site manager
setting the domain of the new site to a non existing domain name
setting the url path of the source site to something like "/2018"
setting the domain of the target site to the original domain and the url path to "/"
When doing a ?fwreinit=true on the url path "/" the following error is thrown:
Error when adding site tree page. You have not supplied a parent page and there is already a root page for the site. There can only be a single root page per site
Calling the source site with the path "/2018" works fine.
The only way to get the new site running is by setting different domainnames in the site settings.
Hey Michi, I'm having trouble reproducing this. What do you mean by "Source site"? The clone feature is mostly just a shortcut to creating a new site. I am able to:
1. Choose clone site
2. Change the path of the new site /2018 (with same domain as original site)
3. Hit clone
Done. You can then update the "original" site to the 2019 content.