Recently someone asked about returning to the Zorin backgrounds instead of his Pictures folder. Over 20 years I have accumulated a folder of wallpapers I prefer to use. In Pictures you can create a folder called "Wallpapers" and add any pictures you wish to use. Right click on an item, and click "Set as wallpaper. The next time you restart, your new background will show. If you right-click the desktop, it will show the contents of your own folder. The menu alongside starts with "Folder". If you wish to return to the Zorin backgrounds, simply click the arrow, and will see a list of sources, which includes "Backgrounds" and "Wallpapers". If you want to add a Zorin one to your list, right-click the image and it will show the source or name of the picture which you can search and save. Sometimes they are heavily edited like "Borealis" and hard to reproduce, but I preferred the original picture.