In the Level browser, there's the option to open The Sandbox, as shown in the above image.
The Sandbox is a fully working level where level changes are not saved.
This level is perfect for testing things, without the hassle of creating and maintaining level of your own.
Other changes, such as scripts, resources or root templates are still stored so you can work in this level.
Editing The Sandbox
The Sandbox is available in every project. If you wish to make permanent changes to this level, then you can load it via the Level browser's "Existing levels" tab:
- Open the level browser to load an existing level
- Enable the "Show inherited levels" filter button
- Find The Sandbox (_TMPL_Sandbox) in the folder "_Shared Templates"
The sandbox level via the existing levels browser, in case you want to make permanent changes.