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<?php $css_current = ['test6' => 1, 'test2' => 2, 'test3' => 3]; $css_original = ['test5' => 5, 'test3' => 3, 'test4' => 4]; $css_result = []; foreach ($css_current as $name => $data) { if (!isset($css_original[$name])) { $css_result[$name] = $data; } } var_dump($css_result); $css_result = []; $css_result = array_diff_key($css_current, $css_original); var_dump($css_result);
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.32, 8.3.0 - 8.3.33, 8.4.1 - 8.4.24, 8.5.0 - 8.5.9
array(2) { ["test6"]=> int(1) ["test2"]=> int(2) } array(2) { ["test6"]=> int(1) ["test2"]=> int(2) }

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