count( $_wp_admin_css_colors ) in user-edit.php not php 8 friendly when int given

[rambillo]

Running WordPress core v6.0 with PHP v8.0.14, all plugins turned off, and a default theme (on a long running installation of WordPress), we're getting:

Fatal error: Uncaught TypeError: count(): Argument #1 ($value) must be of type Countable|array, int given in /.../wp-admin/user-edit.php:303 Stack trace: #0 /.../wp-admin/profile.php(18): require_once() #1 {main} thrown in /.../wp-admin/user-edit.php on line 303

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The code on that line suggests it could be addressed via:

if ( is_countable( $_wp_admin_css_colors ) && count( $_wp_admin_css_colors ) > 1 && has_action( 'admin_color_scheme_picker' ) ) : ?>

[rambillo]

Disregard. The issue was between the seat and the keyboard.

[SergeyBiryukov]

No worries, thanks for the follow-up!

As far as I can tell, this can only happen if a plugin or theme unregisters the default admin colors or overwrites the $_wp_admin_css_colors global.