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<?php $first = [ 'm' => 'n', ]; $second = [ 'm' => 'N', 'M' => 'n', ]; // wtf? var_export( array_diff_uassoc($first, $second, 'strcasecmp') );
Output for 8.1.32 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
array ( 'm' => 'n', )

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