Brief Summary
Use the NSAccentColorName key. Many native macOS applications use the predominant color of their icon to personalize their menus. The purple from the Orion icon could be a nice accent color for the application.
Details:
This will not change the accent color for users who have already defined a color in the system settings. Only users who have selected "Multicolor" will see the custom accent color of Orion.
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Examples of native macOS apps that use an accent color
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