You'll need to show us a screen shot of the LR Library module with the Folders area open.
No update to LR creates folders on your drive for images or imports image into the LR catalog. Updating the LR program and importing images are 2 completely different things.
Above is the screen shot. The top folder is completely new and I have never imported, it contains some pics from a LR course I purchased, there a 20 plus folders that either have LR course folders, or pics I had recently exported. The folders 2018-06-03, 2018-06-04, 2018-06-06 all contain pics I had used for a Slideshow, and are all duplicated from the folders immediately above.
I hope you can help.
Make sure you are using the correct catalog.
No images can magically appear in the LR Catalog file, a Database file, unless the User imported them. That also goes for folders the images are in.
LR is Not a File Manager. It only displays folders and images that the User has imported.
You may be using a catalog that at one time you did import those images and the folder got added because of that.
If during an export you have the option checked to Included in this catalog and then choose to create a new folder, place in a specific folder, then those images will get added to the catalog and the folders you placed them in will get added to the Folders list.
This is completely a User Setting and Option that you have chosen during the exporting of the images.
Not sure how you added images to a slide show but if you exported them to add to the show and had that option selected in the export dialog that is what you are seeing.