When trying to load a world from a newer version, the warning does not give you the option to create a backup, unlike when you upgrade a world to a newer version.

To reproduce

1. Create a world in 20w51a
2. Try to open it in 1.16.5-rc1
   → You only get this warning screen without the option to create a backup

It would be expected to get a similar warning to opening a world from an older version in a newer version, like shown in this screenshot: