Mojave upgrade desktop files disappeared

My wife recently upgraded her desktop Mac to Mojave. Prior to the upgrade, she had a lot of files on her desktop. Those files are now nowhere in sight. We need help finding them.

I understand that Mojave makes use of a feature called "Stacks", and I suspect, based on some things I've read, that that feature is somehow obscuring the "missing" files. I've played around a bit with Stacks, though, and have yet to surface the files.

Within Finder, however, in the Recents view, I find a few of the missing files. I can write click on any one of them, choose "Go to enclosing folder" (or something roughly like that), and find the file. Each such file is now apparently in a folder of it's own, each of which is named with a lengthy hexadecimal string. This suggests to me that Mojave has stashed the files somewhere, but doesn't tell me how to find them.

Any help would be appreciated.

Thanks.