Please explain Projects to me

Please explain Projects in the Photo Library to me. It does not appear to have a stand alone function but is intended to be part of some process. I had been saving special reference photos in a named "Project.’ I never did find a folder location. This Project folder just disappeared. Fortunately all of its files were copies.
What is the intended function of Projects and how do you prevent a Project and its files from disappearing?

What DxO calls “projects” is nothing else than a collection of links leading to each photo collected in the project. No physical copies of RAWs are needed. So my first question to you: did you really copy RAWs?

The well-hidden PDF manual ( is telling a bit more. Reading a manual is always a good idea although it contains sentences like

When you first start using DxO PhotoLab 3, the list of projects will be empty.

Writers of the manual, wake up and do your job… No need to refer to old version numbers in a “PL5_manual”… that’s confusing.

You cannot search within a project and the sorting order is only alphabetical. You also cannot nest projects in a meaningful way. And why projects disappear, I can’t tell you, but I’m not surprised too much. The way DxO has implemented projects let me doubt if anybody involved in their development had a clear idea about “practical use”.