Board Thread:Support Requests - Community Management/@comment-43368626-20191121210855/@comment-34888194-20191121212450

What do you mean? If you meant to create more than one sandbox user subpage, then you create a user subpage. To create a user subpage, you just need to do the following:

User:Unidentified Entity Number 10/ Any time when you add a slash next to the title, it becomes a subpage. Let's just say that you wanted to name your second subpage as User:Unidentified Entity Number 10/sandbox 2 . The third one can be User:Unidentified Entity Number 10/sandbox 3  and so on.

But again, there's really no official way to name your testing page.