1] Use Disk Cleanup to remove Thumbnail files Using the Disk Cleanup tool is one way of fixing the black background problem behind the folder icon by deleting all the Thumbnail files on your disk.

The tools covered in this post work differently ... Once activated, it covers the entire screen with a black background. Now, you can select areas, and only those areas will be visible.

To access everything else, you tap the icon in ... Dynamic Color background has been removed, while the rounded squares are no longer hollow and now filled-in. It’s white or black (depending ...