Once you activate Stacks, it will group the images, PDFs, screenshots and other kinds of files on your Desktop into single icons that look resemble flat, overlaid files. Clicking on a Stack expands its contents, but you can also scroll up and down on a stack to see its contents.
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Here's how to use Stacks to clean your messy desktop. For example, let's start with mine:
1. From the desktop, click View.
2. Select Use Stacks.
3. That messy screen is now clean!
4. Clicking on a stack reveals its contents. Click the empty stack to hide them.
6. To change how Stacks works, click View.
7. Under Group Stacks By, select a sorting option.
8. Scroll up and down on a Stack to browse the images inside, so you can find and open select images.
Congrats, you're a Stack master!