Classic 8×8-pixel B&W Mac patterns

Two years ago I vibe coded a recreation of the Mac Desktop Pattern Control Panel to change a website's background.

Demo here: https://jherrm.github.io/classic-mac-desktop-pattern/

Source: https://github.com/jherrm/classic-mac-desktop-pattern

The other day I realized that holding down the Option key in the System 7 Desktop Patterns control panel changes the button text from "Set Desktop Pattern" to "Set Utilities Pattern". Does anyone here happen to know what that means?

edit: holy crap, I just figured it out: "Set Utilities Pattern" replaces the background pattern of every desk accessory, such as the Calculator and Scrapbook apps, Find File, Key Caps, Puzzle— with the pattern you chose. What a different time that was!