22 White on Black Panel Predicate

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22 | White on Black Panel Predicate
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white-on-black-panel-scheme?

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## 22 White on Black Panel Predicate🔗ℹ

(require mrlib/panel-wob) | package: gui-lib

> procedure (white-on-black-panel-scheme?) → boolean?

This predicate is intended to determine if the underlying operating system is in a dark mode.

Under relatively recent versions of Mac OS, it queries dark mode directly. See also application-dark-mode-handler.

On other platforms, it determines if the foreground color of the panel background is lighter than the background color. If they appear to be the same, white-on-black-panel-scheme? returns #f.

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